### 1 OFFICE OF CHEMICAL SAFETY AND POLLUTION PREVENTION UNITED STATES ENVIRONMENTAL PROTECTION AGENCY

WASHINGTON D.C., 20460



### PC Code: 080801 DP Barcode: 407650

Date: May 14

, 2013

MEMORANDUM

SUBJECT: Registration Review: Preliminary Problem Formulation for Environmental Fate, Ecological Risk, Endangered Species, and Human Health Drinking Water Exposure Assessments for Ametryn

TO: M olly Clayton , Chemical Review Manager Patricia Parrot , Branch Chief Risk Managem ent and Implementation Branch III Pesticide Re

- evaluation Division

FROM: Andrew Sayer, Ph.D., Biologist Cheryl Sutton, Ph.D., Environmental Scientist Environmental Risk Branch I V Environmental Fate and Effects Division (7507P)

REVIEWED BY : Jim Carleton, Ph.D., Senior Fate Scientist Thomas Steeger, Ph.D., Senior Advisor Environmental Risk Branch I V Environmental Fate and Effects Division (7507P)

APPROVED BY : Marietta Echeverria, Branch Chief Environmental Risk Branch I V Environment al Fate and Effects Division (7507P)

The Environmental Fate and Effects Division (EFED) has completed the preliminary problem formulation for the environmental fate, ecological risk, endangered species, and drinking water exposure assessments to be conducted as part of the Registration Review of ametryn , CAS No. 834

- 12

- 8 ; PC Code 080801

. Ametryn is a selective systemic herbicide registered for use on corn, pineapple, and sugarcane

. F unctioning as the first stage of the risk assessment process for Registration Review, this problem formulation provides an overview of what is currently known about the environmental fate and ecological effects associated with ametryn and its degradation

### 2 p roducts. It also describes the preliminary ecological risk hypothesis and analysis plan for evaluating and characterizing risk to non

- target species in support of the R egistration R eview of ametryn . This document also recommends studies that should be co nsidered for inclu sion in a generic data call

- in (DCI) to address uncertainties surrounding the environmental fate and potential ecological effects of ametryn

.

### 3 

# Problem Formulation for the Environmental Fate, Ecological Risk , Endangered Species , and Human Health Drinking Water Exposure Assessments in

Support of the Registration Review of Ametryn

Ametryn : N 2

- ethyl

- N 4

- isopropyl

- 6

- methylthio

- 1,3,5

- triazine

- 2,4

- diamine CAS: 834

- 12

- 8 PC Code: 080801

Prepared by: Andrew Sayer , Ph.D., Biologist Cheryl Sutton

, Ph.D., Environmental Scientist U.S. Environmental Protection Agency Office of Pesticide Programs Environmental Fate and Effects Division Environmental Risk Branch IV 1200 Pennsylvania Ave., NW Mail Code 7507P Washington, DC 20460 Reviewed by: Jim Carleton, Ph.D., Senior Scientist Thomas Steeger, Ph.D., Senior Advisor Approved by: Marietta Echeverria , Branch Chief



### Date: March 7 , 2013

### 4 

## Contents

1. Introduction

................................ ................................ ................................ ......................... 5 2. Conclusions from Previous Risk Assessments

................................ ................................ ... 5 2.1. Ecological Risk Assessments

................................ ................................ ........................ 5 2.2. Drinking Water Exposure Assessments

................................ ................................ ........ 6 2.3. Clean Water Act Programs

................................ ................................ ........................... 6 3. Environmental Fate and Transport

................................ ................................ ...................... 7 3.1. Transformation Products

................................ ................................ ............................. 11 4. Ecological Effects Summary

................................ ................................ ............................. 17 4.1 Toxicity of Ametryn Transformation Products

................................ ................................ . 20 4.1.1 ECOSAR

- Predicted vs. Observed Toxicity Endpoints Relative to Parent Ametryn

..... 21 GS

- 11354 and GS

- 11355

................................ ................................ ................................ ........ 21 NOA 423271

................................ ................................ ................................ ........................... 21 NOA 428383

................................ ................................ ................................ ........................... 22 NOA 438707

................................ ................................ ................................ ........................... 22 G 34048 (2

- hydroxy atrazine)

................................ ................................ ................................ . 22 GS

- 17794 (des

- ethyl hydroxy atrazine)

................................ ................................ .................. 22 4.2. Ecological Incidents

................................ ................................ ................................ .... 24 5. Exposure Pathways of Concern

................................ ................................ ........................ 24 6. Analysis Plan

................................ ................................ ................................ .................... 25 6.1. Stressors of Concern

................................ ................................ ................................ ... 25 6.2. Measures of Exposure

................................ ................................ ................................ . 26 6.3. Measures of Effect

................................ ................................ ................................ ...... 27 6.4. Endangered Species Assessments

................................ ................................ ............... 28 6.5. Endocrine Disruptor Screening Program (EDSP)

................................ ....................... 28 7. Preliminary Identification of Data Gaps

................................ ................................ ........... 29 7.1. Environmental Fate

................................ ................................ ................................ ..... 29 7.2. Ecological Effects

................................ ................................ ................................ ....... 32 8. Refer ences

................................ ................................ ................................ ......................... 35 9. Appendices

................................ ................................ ................................ ........................ 37 Appendix A. Submitted Environmental Fate and Effects Studies

................................ .......... 37 Appendix B. Biological and Economic An alysis Division (BEAD) Report

.......................... 50 Appendix C. Output from OPP Aggregate Incident Database for Ametryn

........................... 52 Appendix D. SIP Results for Evaluate Potential Risk to Birds and Mammals from Drinking Water Exposure.

................................ ................................ ................................ ................ 53 Appendix E. STIR Results to Evaluate the Potential for Inhalation Risk to Birds and Mammals

................................ ................................ ................................ ........................... 54 Appendix F. Environmental Fate and Transport Characterization

................................ ......... 55

### 5 

# 1. Introduction

The purpose of this problem formulation is to provide an understanding of the environmental fate and ecological effects of the registered uses of ametryn in support of Registration Review. Ametryn belongs to the triazine clas s of herbicides; the mode of action is through inhibition of the photosynthesis II pathway

. Ametryn is a selective systemic herbicide, absorbed by the leaves and roots, with translocation through the xylem of vascular plants. The compound is used for sele ctive control of broadleaf and grassy weeds (pre

- and post

- emergent)

. According to the Reregistration Eligibility Decision (RED) document completed in 2005 (USEPA 2005) 1 

### a metryn was first registered for use to control broadleaf weeds and annual grasses in sugarcane fields in 1964. In 1969, use for general weed control in corn fields, currently the largest use of ametryn, was added. Other crop uses added to the registration include bananas, grapefruit, oranges, pineapple, plantains, and potatoes for broad leaf weed, annual grass, and general weed control and as a desiccant. Ametryn has also been used as a general herbicide in uncultivated areas, rights of way, and industrial areas and aquatic weeds. Over time, the uses of ametryn have been cancelled so th at only four use sites remain: field corn, popcorn, pineapple, and sugarcane.

Ametryn is formulated as water dispersible granules and can be applied by conventional ground
sprayers for use on sugarcane, corn (pop and field), and pineapples (Hawaii only)

. Aerial application is allowed only for use on sugarcane in Florida

. The S creening L evel Usage

e stimates (USEPA 2012) of agricultural uses of ametryn are corn at 100,000 lbs a

. i

. and sugarcane at 80,000 lbs a

. i

. which average < 1 and 30 percent of the crop total, respectively (data not available for pineapple). There were no uncultivated areas indicated in the Screening Level Usage estimates. More complete details are available in Appendix B

.

Between 2000 and 2005, the crops w ith the most use in terms of pounds of active ingredient applied were field corn (65%) and sugarcane (35%). During the 2006

- 2010 timeframe the same two crops accounted for the major ity of use (field corn 51%, and sugarcane 49%), even though total pounds active ingredient a pplied decreased from the amount applied during the 2000

- 2005 timeframe. Maximum single application rates for corn (field and pop), pineappl e, and sugarcane are: 1.6 , 1.6 , and 2.4 lbs a.i./A, respectively. There are no residential, pub lic health

, or other

non

- food registered uses of ametryn

. Further details on ametryn usage profile and history are provided in the Biological and Economic Analysis Division ( BEAD ) Chemical Profile ( USEPA 2012, Appendix B ).



# 2. Conclusions from Previous Risk Assessments

**2.1. Ecological Risk Assessments** 

1 USEPA. 2005. Reregistration Eligibility Decision (RED) for Ametryn. Office of Chemical Safety and Pollution Prevention formerly Prevention, Pesticides and Toxic Substances. EPA 738

- R

- 05

- 006. September 2005. http://www.epa.gov/oppsrrd1/REDs/ametryn_red.pdf

### 6 The environmental fate and e cological r isk a ssessment for the re

- registration of ametryn was issued in June 2005 (USEPA 2005b) . The assessment indicated exceedance of the risk level of

concern ( LOC ) (RQ ≥1) for listed non

- target terrestrial and aquatic plants. Although ametryn is practically non

- toxic to birds and is only slightly toxic to mammals on an acute exposure basis, the chemical’s high application rates resulted in risk quotients (RQs) that exceede d the acute risk to listed species level of concern (LOC; RQ ≥ 0.1) for mammals

, and the chronic risk LOC (RQ ≥1) for birds. For aquatic animals, the assessment indicated exceedance of the chronic risk LOC (RQ ≥1) for estuarine/marine fish and invertebrates.



## 2.2. **Drinking Water Exposure Assessments**

The Environmental Fate and Effects Division (EFED) conducted a revised drinking water assessment (DWA) for ametryn in 2005 (USEPA 2005a) following proposed reductions in the maximum application rate by the regi strant in response to the Draft RED. The residues of concern considered in that DWA were parent ametryn and t wo of its transformation products ( see Table 3 ) GS

- 11354 and GS

- 11355. In the Human Health Drinking Water Assessment included in the final Environmental Fate and Ecological Risk Assessment for the Re

- registration of Ametryn (USEPA 2005b), in addition to parent, GS

- 11354 and GS

- 11355, the transformation products NOA423271 and NOA428383 were included as residues of concern. These compounds, whi ch are primarily formed through aerobic soil metabolism of ametryn, were identified in coordination with the Health Effects Division as being of possible toxicological concern based on their structural similarity to parent ametryn and, in the case of NOA42 3271 and NOA428383, on the fact that they are oxidized forms of ametryn and able to be reduced back to parent under environmental conditions where redox potential is below

- 148 mV. As recommended by HED, the transformation products G

- 34048, GS

- 17794, and NOA 438707 were not considered in the DWA, based on a separate risk assessment for atrazine metabolites which concluded that these hydroxy transformation products did not raise toxicity concerns and were only expected to be present at low levels in drinkin g water.

The uses assessed in 2005 were corn, pineapple and sugarcane, although a surface water estimated drinking water concentration (EDWC) for pineapple was not determined due to a lack of an appropriate modeling standard scenario. The maximum EDWC w as associated with Louisiana ( LA ) sugarcane use adjusted using the national percentage crop area (PCA) default factor of 0.87 . The 1

- in

- 10 year acute EDWC was 91 μg/L, and the 1

- in

- 10 year chronic EDWC

was 19.9 μg/L ; the 30

- year daily average EDWC was 14. 4 μg/L. The maximum groundwater EDWC, associated with sugarcane use in HI, was 9.2 μg/L.



## 2.3. **Clean Water Act Programs**

Ametryn is not identified as a cause of impairment for any water bodies listed as impaired under section 303(d) of the Clean Water Ac t 2 

### . In addition, no T otal Maximum Daily Loads (TMDL)

2 http://iaspub.epa.gov/tmdl_waters10/attains_nation_cy.cause_detail_303d?p_caus e_group_id=885

### 7 have been developed for ametryn 3



### . The Impaired Waters and Total Maximum Daily Loads website can be consulted for more information 4



### . EPA a quatic benchmarks , based on the 1996 RED document, have been established for ametryn 5



### . The Agency invites submission of water quality 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 Assessment and Management Process 6 

### , in order to ensure they can be used quantitatively or qualitatively in pesticide risk assessments.



# 3. Environmental Fate and Transport

Although, based on limited data, ametryn is classified as nonpersistent to slightly persistent ( scale of Goring et al. , 1975 ) in aerobic soil s ; however, the chemical is sufficiently mobile that it
may migrate into anaerobic co m partm ents, where available da ta suggest that it will be substantially more persistent. D ue to a lack of adequate data

, the persistence of the compound in aerobic aquatic environments is uncertain ; however

, data are sufficient to demonstrate that ametryn is stable to abiotic hydrolysis at environmental pHs. D ue to a lack of adequate data

, i t is uncertain whether the compound photodegrade s in water or soil.

A metryn is classified as mobile to moderately mobile in soils, under the Food and Agricul ture Organization (FAO) mobility classification scheme

. In leaching studies, ametryn leached through sandy loam, loam and sand soil columns, and was detected in the leachate. In a clay soil column, ametryn was less mobile, but was still detected at a dep th of 8 inches and at low levels in the leachate. Although there are no batch equilibrium data for the transformation products of ametryn, in aged soil column studies, all of the transformation products monitored (GS

- 34048; GS

- 11354; GS

- 11355; GS

- 26831; G S

- 32083 ; GS

- 28304; and GS

- 17794; see Table s 2 and/or 5 for identifications) leached through sandy loam soil, and all except GS

- 17794 were detected in the leachate. All of the transformation products studied were more mobile than the parent

, and have the potential to leach to groundwater. There are no mobility data on major transformation products NOA 423271 and NOA 428383.

Ametryn is not expected to volatilize from dry or wet soils or from water, based on its low volatility (vapor pressure of 2.74 x10 - 6 

### torr) and Henry’s Law constant (2.43 x 10 - 9 

### atm· m 3 

### ·mole - 1 ). 

### Ametryn is fairly soluble in water (200 ppm at 25°C)

, and based on its octanol

- water partition coefficient ( log K ow 

### = 2.63) and fish bioconcentration factor (BCF) of 83X

, is not expected to bioconcentrate in fish

. Ametryn may potentially reach surface water via spray drift, runoff , and /or subsurface lateral transport . In the environment, the major known route of degradation of ametryn is aerobic

3 http://iaspub.epa.gov/tmdl_waters10/attains_nation.tmdl_pollutant_detail?p_pollutant_group_id= 885&p_pollutant_ group_name=PESTICIDES
4 http://www.epa.gov/owow/tmdl /
5 http://www.epa.gov/oppefed1/ecorisk_ders/aquatic_life_bench mark.htm

. 6 http://www.epa.gov/oppfead1/cb/ppdc/2006/november06/session1

- sop.pdf

### 8 metabolism in soils (t 1⁄2 

### = 9.6 to 38 days). In anaerobic soil and aquatic environments, ametryn is persistent. Given its mobility, transport to groundwater of ametryn a s well as some of its transformation products is also likely

, as a consequence of normal agricultural use.

S ubmitted terrestrial field dissipation studies did not provide much useful information on the fate of ametryn, due to issues such as inadequate sampling (depth and times), lack of monitoring for all major transformation products , variable data, and applica tions at less than the maximum rate

. T he studies did however indicate that both ametryn and its transformation product G

- 34048 (2

- hydroxy atrazine) are susceptible to leaching in the field, with G

- 34048 being detected at depths
up to 48 inches.

There are multiple transformation products formed in fate studies; these are presented in detail in Section 3.1

. Table 1 provides a summary of physical/chemical properties and environmental fate parameters of ametryn. Additional details of individual studies are di scussed in Appendix F

.

Table 1 . Physical/Chemical Properties and Environmental Fate Parameters of Ametryn.

Parameter Value Description/ Comments Reference, Study classification
Chemical Classification Triazine

--

MRID 40885812 and USEPA 2005 Molecular Formula C 9 H 17 N 5 S

--
PC Code 080801

-- Chemical Name (IUPAC) N 2

- ethyl

- N 4

- isopropyl

- 6

- methylthio

1,3,5

- triazine

- 2,4

- diamine --
Chemical Name (CAS) N

- ethyl

- N '

- (1

- methylethyl)

- 6

- (methylthio)

- 1,3,5

- triazine

- 2,4

- diamine --

CAS Number 834

- 12

- 8

--
Pesticide Classification Herbicide (systemic)

-- Molecular Weight 227.3

--

Physical State White powder

-- Water Solubility (ppm) 185 at 20 o C 200 at 25 o C (pH 7) -- Vapor pressure (25 o C) 2.74 x10 - 6 torr

-- Henry's Law Constant (25 o C) 2.43 x 10 - 9 atm· m 3 ·mole - 1 Calculated

Octanol/Water Partition, K ow 4.27 X 10 2 (log K ow = 2.63) PPDB http://sitem.herts. ac.uk/aeru/iupac/2 7.htm Persistence
Hydrolysis Stable at pH 5, 7, 9

-- MRID 40995812, Acceptable

### 9 Parameter Value Description/ Comments Reference, Study classification

Direct photolysis in water at pH 7 No acceptable data. Data insufficient to determine photodegradation.

Data are needed. MRID 41169601

, Not Acceptable

(reclassified)

Photolysis on soil No acceptable data. Data insufficient to determine photodegradation. MRIDs 41169602, 41169603 Not Acceptable

(reclassified)

Aerobic soil metabolism No acceptable data. Inadequate analytical method. Accession No. 146399 Not Acceptable

No acceptabl e data. Inadequate analytical method. Acc ession No. 255735 Not Acceptable
t 1⁄2 = 38.9 days for ametryn (parent only) in sandy loam soil at 25°C

t 1⁄2 = 51.0 days for total toxic residues used in DWA (ametryn plus GS11354 and GS

- 11355; transformation products NOA423271 and NOA428383 were not monitored) Slightly persistent*

Single soil. Data from additional soils (3) are needed. MRID 41752401 1 Acceptable

t 1⁄2 = 9.6 days (parent only) in loam soil from Switzerland at 20°C

t 1⁄2 = 29.2 days for total toxic residues used in DWA (ametryn plus GS

- 11354 and GS

- 11355)

Unextracted residues were 20% by 14 days, 41% by 56 days, and 64% by 171 days. Nonpersistent*

Half

- life may be underestimated due to unexplained high levels of unextracted residues. MRID 46533801 2 Supplemental

Anaerobic soil

metabolism Ametryn was stable to anaerobic degradation in a sandy loam soil at 25°C. Parent ametryn increased during the flooded phase due to reduction of a degradate(s) back to the parent

. A half

life was not determined. Persistent under anaerobic (flooded) conditions. The potential transformation products NOA 432271 ( sulfoxide of ametryn) and NOA 428383, were not monitored. MRID 41752401 Acceptable

Ametryn was stable to anaerobic degradation in a loam soil from Switzerland at 20°C. Parent ametryn increased during the flooded phase. A half

- life was not determined.

Unextracted residues were 20% at flooding, and 31

- 35% at 28

- 150 days. Persistent und er anaerobic (flooded) conditions. It is possible that NOA 423271 underwent reduction and reformed parent ametryn under flooded conditions. MRID 46533801 Supplemental

### 10 Parameter Value Description/ Comments Reference, Study classification

Aerobic aquatic

metabolism No data Data are needed Data Waiver was granted in D342463 (9/15/07).

Data are now considered
necessary.

Anaerobic aquatic metabolism t 1⁄2 = 1386 days in pond water/loam sediment (pH 7.2) at 20°C

Unextracted residues were <6.8% throughout the study. Persistent MRID 46533801 Supplemental

Stable in clay loam sediment (pH 6.5) at 25°C

Unextracted residues were 14

- 17% at 360 days. Persistent MRID 42861603, Acceptable

Field Dissipation

Terrestrial field

dissipation No half

- life available. Validity of data was questionable due to high variability, and inadequate sampling. MRID 255735 Not Acceptable

Biphasic dissipation which slowed after 60 days on a bareground plot of sand soil in IL (at 2.0 lb a

. i

. /A). Ametryn was detected to 12 inches. G

- 34048 was detected at all depths to 48 inches. Inadequate sampling (depth and times), all major transformation products not monitored, variable data, maximum application rate not used. MRID 41872301 Supplemental

Biphasic dissipation (slowed after 30 days) observed in a sand soil in IL (at 4.0 lb a

. i

. /A) planted to corn. Ametryn was detected to 12 inches. G

- 34048 was detected at all depths to 48 inches. Inadequate sampling (depth and times), all major transformation products not mon itored, variable data, maximum application rate not used. MRID 41872302 Supplemental

Biphasic dissipation which slowed after 60 days in a silty loam sugarcane field in LA (at 2.5 lb a

. i

. /A x 2 applications).

Ametryn, GS

- 13354 and GS

- 17794 were not detected below 6 inches. G

- 34048 was detected below 6 inches twice (0.014

- 0.015 ppm at 20 and 60 days). All major transformation products not monitored, variable data, maximum application rate not used. MRID 417524 02 Supplemental

Mobility

### 11 Parameter Value Description/ Comments Reference, Study classification

Adsorption/Desorption Adsorption K oc = 927, 205, 96, 257 mL/g oc K d = 26.2, 1.1, 1.1, 1.2 mL/g

Desorption K oc = 983, 570, 307, 990 mL/g oc K d = 27.8, 3.0, 3.4, 4.66 mL/g

1/n = 0.76

- 0.93 (ads) 1/n = 0.80

- 1.0 (des) Soils studied (pH, % o.m.)/Mobility class 3 :
MD Clay (5.9, 4.8%)/mod. mobile; MD Sand (6.5, 0.9%)/mod. mobile; MD Sandy loam (7.5, 1.9%)/mobile; CA Loam (6.7, 0.8%)/mod. mobile MRID 40995813 Acceptable

Unaged ametryn was detected at all depths and in leachate from sandy loam (1.9% om), loam (0.8% om), and sand (0.9% om) soil columns. In a clay (4.8% om) soil column, 91% of the applied remained in the top 1

- inch, although some residues leached to 8 inches and up to 0.14% of the applied was detected in leachate. Paren t Ametryn has the potential to leach in multiple soil types. MRID 41169604 Acceptable

Aged ametryn and its transformation products (GS

- 34048; GS

- 11354; GS

11355; GS

- 26831; GS

- 32083 ; GS

- 28304; and GS

- 17794) were mobile in sandy loam soil (1.9% om). All except GS

17794 were detected in the leachate. All transformation products were more mobile than the parent. Residues were not characterized post

aging. Study concluded that both amet ryn and its transformation products should be considered potential groundwater contaminants. MRID 41169605 Supplemental

Fish Bioconcentration

Bioconcentration in fish (BCF) 61X in edible tissues 110X in non

- edible tissues 83X in whole fish

Approximately 60

- 80% of the accumulated residues were eliminated from fish after 28 days of depuration. Based on study results and a K ow of 4.3 X 10 2 (log K ow = 2.6), ametryn residues are not likely to bioconcentrate in fish tissues. MRID 42061901 Acceptable

1 MRID 41752401 contained studies for both aerobic and anaerobic soil metabolism. 2 MRID 46533801 contained studies for aerobic and anaerobic soil metabolism and anaerobic aquatic metabolism. 3 Mobility class based on Food and Agriculture Organization soil mobili ty classification scheme (FAO, 2000).

*Goring et al. 1975 scale was used to describe persistence. Nonpersistent: t1⁄2 < 15 days; slightly persistent t1⁄2 15

- 45 days; moderately persistent t1⁄2 45

- 180 days; persistent t1⁄2 >180 days.



## 3.1. **Transformation Products** 
Table 2 summarizes the major and/or toxicologically significant transformation products and their maximum amounts formed in the fate studies, and identifies which compounds will be assessed in the ecological risk assessment to be conducted for ame tryn as part of the Registration

### 12 Review process. The toxicity of specific transformation products is discussed in detail in Section 4.3

. The transformation products of ametryn in the submitted environmental fate studies include 2,4

- diamino

- 6

- methylthio

- s

- triazine (GS

- 26831), 2

- amino

- 4

- isopropylamino

- 6

- methylthio

- s

- triazine (GS

- 11354), 2

- ethylamino

- 4

- amino

- 6

- methylthio

- s

- triazine (GS

- 11355), 2

- hydroxy

4

- ethylamino

- 6

- isopropylamino

- s

- triazine (G

- 34048), 2

- ethylamino

- 4

- isopropylamino

- s

- triazine (GS

- 32083), 2

- amino

- 4

- isopropylamino

- s

- triazine (GS

- 28304), 2

- amino

- 4

- isopropylamino

- 6

- hydroxy

- s

- triazine (GS

- 17794), N

- ethyl

- N

- isopropyl

- 6

- methanesulfinyl

- [1,3,5]triazine

- 2,4

- diamine (NOA 423271), 4

- Ethylamino

- 6

- isopropylamino

- [1,3,5]triazine

- 2

- sulfinic acid sodiu m salt (NOA 428383), 4

- Hydroxy

- 6

- isopropylamino

- [1,3,5]triazin

- 2

- ylamino

- acetic acid (NOA 438707), and carbon dioxide.

### 13 Table 2

. Ametryn and Its Major and/or Toxicologically Significant Environmental Transformation Products from Laboratory Studies

Code Name/ Synonym Chemical Name(s) Chemical Structure Study Type Ref. (MRID) Maximum(s) %AR 1 (day) Final %AR (last detection day or study length)
PARENT

Ametryn 2 CAS No.: 834

- 12

- 8 CAS Name(s): N

- e thyl

- N

- (1

- methylethyl)

- 6

- (methylthio)

- 1,3,5

- triazine

2,4

- diamine OR 2

- ( e thylamino)

- 4

- (isopropylamino)

- 6

- (methylamino)

- S

- triazine

SMILES String: CCNc1nc(nc(n1)SC)NC(C) C (ISIS v2.3/Universal SMILES). CCNc1nc(NC(C)C)nc(SC) n1 (EPI Suite, v3.12)
MAJOR TRANSFORMATION PRODUCTS N

N N NH

NH S

### 14 Code Name/ Synonym Chemical Name(s) Chemical Structure Study Type Ref. (MRID) Maximum(s) %AR 1 (day) Final %AR (last detection day or study length)

GS

- 11354 CAS Name(s): 2

- amino

- 4

- isopropylamino

- 6

- methylthio

- s

- triazine ( Also: de

- isopropyl prometryn)



### . Aerobic soil metabolism 41752401 11.9% (14) 2.3% ( 365 )

Aerobic soil metabolism 46533801 1.9% (14) 0.1% (56 )

A na erobic soil

metabolism 41752401 9.5 % (62) 9.5 % (62 )

A na erobic soil

metabolism 46533801 2.4% (14) 2.2% (150 )

A na erobic

aquatic metabolism 46533801 1.6% (56) 1.3% (120 )

GS

- 11355 CAS Name(s): 2

- ethylamino

- 4

- amino

- 6

- methylthio

- s

- triazine Aerobic soil metabolism 41752401 1. 9 % (3 65 ) 1.9% (365)

Aerobic soil metabolism 46533801 1.2% (14) 0.5% (171 )

A na erobic soil

metabolism 46533801 GS

- 11355 plus

an unknown : 1.8 % (through 150 d) 2.3% (150)

A na erobic

aquatic metabolism 46533801 0.5% (91

- 121) 0.5% (120)

### 15 Code Name/ Synonym Chemical Name(s) Chemical Structure Study Type Ref. (MRID) Maximum(s) %AR 1 (day) Final %AR (last detection day or study length)

NOA 423271 2 CAS N ame ( s ): n

- ethyl

- n

isopropyl

- 6

- methaneslfinyl

- [1,3,5]triazine

- 2,4

- diamine (sulfoxide of ametryn) Aerobic soil metabolism 46533801 24.7 % (7) 0.2% (171)

A na erobic soil

metabolism 46533801 20.6% ( 0 d post

flood) 0.1% (56 )

NOA 428383 2 CAS Name(s): 4

- ethylamino

- 6

- isopropylamino

- [1,3,5]triazine

- 2

- sulfinic acid sodium salt Aerobic soil metabolism 46533801 14.8 % ( 28 ) 1.6% (171 )

A na erobic soil

metabolism 46533801 13.5% (7 d post

flood) 8.6% (150 )

NOA 438707 CAS Name(s): 4

- Hydroxy

6

- isopropylamino

- [1,3,5]triazin

- 2

- ylamino

acetic acid Aerobic soil metabolism 46533801 10.3

- 10.6% ( 56

- 91 ) 7.5% (171 )

A na erobic soil

metabolism 46533801 3.1% (28) 2.0% (150 )

G 34048 CAS Name(s): 2

- ( e thylamino)

- 4

- hydroxy

- 6

- (isopropylamino)

- s

- triazine (synonym: 2

- hydroxy atrazine) Aerobic soil metabolism 41752401 2.6 % (total for G 34048 plus G

1779 4 ) (92 ) 1.2% (365)

Aerobic soil metabolism 46533801 18.1% (28) 0.2% (171 )

A na erobic soil

metabolism 46533801 15.4% (150) 15.4% ( 150 )

A na erobic

aquatic metabolism 46533801 0.7% (56) 0.5 (120) 

### N

N N OH

NH NH

### 16 Code Name/ Synonym Chemical Name(s) Chemical Structure Study Type Ref. (MRID) Maximum(s) %AR 1 (day) Final %AR (last detection day or study length)



### CO 2 CAS No : 124

- 38

- 9 SMILES String: C(=O)=O Aerobic soil metabolism 46533801 27.4

- 28.9% (120

- 171 ) 27.4% (171 )

A na erobic soil

metabolism 46533801 1.2 % (150 ) 1.2% (150 )

1 AR = Percentage of Applied Radioactivity; 2 = To be included in the ERA.

### 17 

# 4. Ecological Effects Summary

Table 3 and Table 4 provide summar ies of the toxicity endpoints for aquatic and terrestrial organisms, respectively. These values represent the most sensitive species tested within each tax on to characterize potential acute and chronic effects of ametryn

. In addition, the table s provide a preliminary overview of the potential acute toxicity of ametryn , by providing the acute toxicity classifications.

Based on the most sensitive toxicity endpoints

, ametryn is classified as moderately toxic
to freshwater fish (and aquatic

- phase amphibians for which fish serve as surrogates) and slightly toxic t o freshwater invertebrat es on an acute exposure basis. Chronic toxicity studies with freshwater fish indicated reduced growth as the most sensitive measurement endpoint

. Chronic exposure to freshwater invertebrates resulted in reduced reproduction.

Ame tryn is classified as moderately toxic to estuarine /marine fish and invertebrates on an acute exposure basis

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

, and previous estimates of chronic toxicity were based on acute

- to

chronic ratios derived using toxicity data for freshwater species. Chronic toxicity data for estuarine/marine invertebrates indicated reduced growth and reproduction . Compared to freshwater invertebrates, estuarine/marine invertebrate s exhibited toxicity values an order of magnitude less (more toxic)

. Toxicity testing with a quatic plants indicated over a 500

- fold difference in the sensitivity of vascular plants compared (NOAEC=0.002 mg/L) to non

- vascular algae (NOAEC=1.14 mg/L)

. Ametryn is classified as practically non

- toxic to birds (and to terrestrial

- phase amphib i ans and reptiles for which birds serve as surrogates) on both an acute oral and subacute dietary exposure basis ; the compound is slightly toxic to mammals on an acute exposure ba sis. Chronic exposure to ametryn resulted in reduced growth and reproduction in birds and reduced growth in mammals.

A metryn is classified as practically non

- toxic to honeybees ( Apis mellifera ) on an acute contact exposure basis.

T errestrial plant see dling emergence showed oat and cucumber as the most sensitive monocot and dicot, respectively. Vegetative vigor showed onion and cucumber as the most sensitive monocot and dicot, respectively.

### 18 Table 3 . Summary of the M ost S ensitive E ndpoints from A quatic T oxicity S tudies for Ametryn

Taxonomic

Group Study Type Surrogate Species Toxicity Value (all units in terms of measured active ingredient) Acute Toxicity Classification Source Classification

Freshwater fish 1 Acute Rainbow Trout ( Oncorhynchus mykiss ) LC 50 = 3.6 mg/L Moderately toxic MRID 428616 02 Acceptable

Chronic (Early Life

Stage) Fathead Minnow ( Pimephales promelas ) NOAEC = 0.7

m g/L LOAEC = 1.4

m g/L Effects : r educed growth -- MRID s 41189703, 423252 03 Acceptable

Freshwater invertebrates Acute Water Flea ( Daphnia magna ) LC 50 = 28 mg/L Slightly toxic MRID 409958 06 Acceptable

Chronic Water Flea ( Daphnia magna ) NOAEC = 0.24
mg /L LOAEC = 0.32

m g/L Effects : reproduction

, female body length, male dry

body weight, female dry body weight -- MRID 41189702, 423252 02 Supplemental 2

Estuarine/ marine fish Acute Sheepshead Minnow ( Cyprinodon variegatus ) LC 50 = 5.8 mg/L Moderately toxic MRID 411149 02 Acceptable

Estuarine/ marine invertebrates Acute Mysid ( Americamysis bahia ) L C 50 = 2.3 m g/L Moderately toxic MRID 411149 01 Acceptable

Chronic Mysid ( Americamysis bahia ) NOAEC = 50 μg/L LOAEC = 97 μg/L Effects : male and

female body weight, female body length, number of female offspring, number

of offspring per reproductive day -- MRID 473990 01 Acceptable

Aquatic plants and algae Vascular Duckweed ( Lemna gibba ) NOAEC = 0.002

m g/L EC 50 = 0.013 m g/L -- MRID 473990 02 Acceptable

Non

vascular Green Algae ( Pseudokirchneriell a subcapitata

formerly Selenastrum capricornutum ) NOAEC = 1.14 μg/L EC 50 = 3.67 μg/L -- MRID 409958 10 Supplemental 3

1 Freshwater fish represent surrogates for aquatic

- phase amphibians.
2 The study was class ified as supplemental due to no statistically significance difference in length between the solvent control and any of the treatments.

### 19 3 MRID 40995810 is an acceptable study . However, in addition to this study, additional studies are required to fulfill guideline 850.4500

.



### Table 4 : Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for Ametryn

Taxonomic

Group Study Type Surrogate Species Toxicity Value (all units in

terms of measured active ingredient) Acute Toxicity Classification Source Classification

Birds 1 Acute Bobwhite Quail ( Colinus virginianus ) LD 50 = >2250 mg/ kg

- bw Practically N on

- toxic MRID 409958 01 Acceptable

Sub

acute dietary Mallard Duck ( Anas platyrhynchos ) LD 50 = >5620 mg/ L NOAEC= <562 mg/L Practically Non

- toxic MRID 409958 02 Acceptable

Sub

acute dietary Bobwhite Quail ( Colinus virginianus ) LD 50 = >5620 mg/L NOAEC = 1780 mg/L Practically Non

- toxic MRID 409958 03 Acceptable

Chronic Mallard Duck ( Anas platyrhynchos ) NOAEC = 300 mg/kg

- diet LOAEC = 900 mg/kg

- diet Effect s : Adult body weight, egg s laid, cracked eggs, offspring survivors -- MRID 415476 02 Acceptable

Chronic Northern bobwhite quail ( Colinus virginianus ) NOAEC = 300 mg/kg

- diet LOAEC = 900 mg/kg

- diet Effects : Adult body weight, egg production -- MRID 415476 01 Acceptable

Mammals Acute oral Laboratory
rat ( Rattus norvegicus ) LD 50 = 1356 mg/kg

- bw (males) LD 50 = 1009 mg/kg

- bw (females) Slightly Toxic MRID 409958 14 Acceptable

Chronic Laboratory
rat ( Rattus norvegicus ) NOAEL = 14 mg/kg/day (males) 14

- 26 mg/kg/day (females) LOAEL = 131 mg/kg/day (males) 134

- 138 mg/kg/day (females) -- MRID 403499 05 Acceptable

Insects Acute
contact Honey bee ( Apis mellifera L. ) LD 50 = >100 μg/bee Practically

non

- toxic MRID 409958 11 Acceptable

### 20 Taxonomic

Group Study Type Surrogate Species Toxicity Value (all units in

terms of measured active ingredient) Acute Toxicity Classification Source Classification

Terrestrial Plant T oxicity Tier II: Seedling
emergence Monocot: oat 21

- day EC 25 = 0.083 lb/A 21

- day NOEC = 0.05 lb/A (based on dry weight)

-- MRID 409958 0 8 Acceptable

Dicot: cucumber 7 21

- day EC 05 = 0.0002 lb/A 21

- day EC 25 = 0.002 7 lb/A 21

- day NOEC = <0.002 lb/A (based on % of seedlings emerged )

Terrestrial Plant Toxicity Tier II Vegetative vigor Monocot: onion 21

- day EC 25 = 0. 105 lb/A 21

- day NOEC = 0.05 lb/A (based on dry weight )

-- MRID 409958 0 9 Acceptable

Dicot: lettuce 8 28

- day EC 0 5 = 0.001 lb/A 28

- day EC 25 = 0.006 lb/A 28

- day NOEC =

< 0.006 lb/A (based on dry weight )

1 Birds represent surrogates for terrestrial

- phase amphibians and reptiles. Since the NOEC was greater than the EC25, a EC05 was calculated


### In 2007, EPA granted a waiver request for an estuarine/marine fish early life stage toxicity test (guideline 850.1400) 9



### . EFED determined that although there was uncertainty regarding the use of the acute

- to

- chronic ratio (ACR), the use of the ACR did not result in an RQ that was above the LOC.



## 4

**. 1**  **Toxicity of Ametryn**  **Transformati on**  **P roducts** 

I n addition to parent ametryn, available environmental fate data indicate that the transformation products GS

- 11354, GS

- 11355, NOA 423271, NOA 428383, NOA

7 The IC 05 value was calculated because the NOEC was non

- definitive and approximately the value of the EC 25 . The EC 05 is required for endangered species assessments.
8 The IC 05 value was calculated because the NOEC was non

- definitive and approximately the value of the EC 25

. The EC 05 is required for endangered species assessments.
9 EFED Response to Waiver Request for Estuarine/Marine Fish Early Life Stage Study and Aerobic Aquatic Metabolism Study. Date: 09/15/2007. DP Barcode: D342463.

### 21 438707, G 34048, GS

- 17794 may be present in the environment following use of ametryn

. I n the absence of toxicity data, predicted acute and chronic toxicity values for the major transformation products of ametryn were estimated using EPA’s ECOSAR tool (v 1.1) 10 

### which is based on quantitative structure activity relationships (QSAR) for effects on fish, daphnids, and green algae. Predicted toxicity values were also generated for parent ametryn and compared to observed endpoints from registrant

- submitted studies to assess confidence in ECOSAR predict ions of the toxicity of ametryn’s transformati on products

. ECOSAR

- predicted and observed toxicity values for ametryn and its major transformation products are provided in Table 5 . If available, observed toxicity endpoints for transformation products of other triazines that are closely related ( i.e ., have similar structures) to ametryn transformation products were also examined

.

4.1 .1 ECOSAR

- Predicted vs. Observed Toxicity Endpoints Relative to Parent Ametryn

ECOSAR

- predicted toxicity values for parent ametryn we re roughly an order of magnitude less (more toxic) than measured toxicity endpoints for dap hnids and mysids

. In contrast, ECOSAR predicted toxicity values for parent ametryn were appr oximately an order of magnitude greater (less toxic) than the observed toxicity endpoint for freshwater

a nd estuarine/marine fish and g reen algae

. Other triazine compounds exhibited similar ECOSA R

- predicted toxicity value s

. T oxicity values for parent prometon were 1

- 2 orders of magnitude l ower than observed prometon toxicity endpoints for fish, daphnids, and mysi ds, and were roughly 3 times less than the observed toxicity endpoint fo r green algae

.
GS

- 11354 and GS

- 11355
While the basic structure is similar to ametryn, d e

- ethylation from the 2

- amino group of the parent produces GS

- 11354. GS

- 11354 is also a transformation product of other triazine herbicides including prometryn. GS

- 11355, d e

- isopropyl ametryn

, also has a structure similar to ametryn with the isopropyl group absent from the 4

- amino moiety

. The ECOSAR

- estimated toxicity values indicate that both GS

- 11354 and GS

- 11355 are less toxic than parent ametryn to a ll aquatic taxa exc ept for green algae. Neither of these transformation product s will be considered stressor s of concern in the Registration Review ecological risk assessment.

NOA 423271 Oxidation of the methylthio group of ametryn (

- SCH 3 

### ) to a sulfoxide (

- SOCH 3 

### ) results in the minor degradation product NOA 423271 ( ametryn sulfoxide)

. The ECOSAR

estimated toxicity values indicate that the observed toxicity values are lower (indicating higher toxicity) than observed ametryn values for marine fish and invertebrates, and freshwater invertebrates

. ECOSAR values were greater (less toxic) than parent ametryn for freshwater fish and green algae. This compound is formed through ae robic soil metabolism, but may be reduced back to the parent form under certain environmental

10 http://www.epa.gov/oppt/newchems/tools/21ecosar.htm

### 22 conditions. Therefore, EPA will consider it a stressor of concern for ecological risk, and will assume that the toxicity of this degradation product is equal to that of the parent.

NOA 428383 In this degradate t he methyl group in the 6

- methylthio moiety of ametryn has been replaced by three oxygen atoms with a net negative charge . ECOSAR

- estimated toxicity endpoints for th is degradate predict it to be less toxic than the parent ametryn. This degradate is formed by aerobic soil metabolism, but may be reduced back to the parent under certain environmental conditions. Therefore, EPA will consider NOA 428383 as a
stressor of concern for e cological risk. The toxicity of this degradation product will be assumed equal to that of the parent.

NOA 438707 Degradate NOA 438707 is formed from a hydroxyl group substitution of the ametryn 4

- methylthio group , and modification of the 2

- ethyamino group to a carboxylic acid (acetic acid). The ECOSAR

- estimated toxicity values for this degradate indicate it is less toxic than the parent ametryn . EPA will not consider NOA 438707 as a stressor of concern for risk assess ment.

G 34048 ( 2

- hydroxy atrazine)
The substitution of t he 2

- methy lthio group to a hydroxyl group results in the formation of the major transformation product G 34048 , known as 2

- hydroxy atrazine . ECOSAR

estimated toxicity values indicate that G 34048 is less toxic than parent ametryn to a ll aquatic taxa excluding green algae. EPA will not consider G 34048 as a stressor of concern for risk assessment.

GS

- 17794 ( d es - ethyl hydroxy atrazine)
Removal of an ethylamino group from parent ametryn, and replacement of the thiomethyl
group with a hydroxyl group forms GS

- 17794 , which was only present as a minor transformation product (≤1.7%) in two soil metabolism studies

. GS

- 17794 is also a degradate of atrazine ( i.e.
, deethylhydroxyatrazine; OIAT/ DHEA ), propazine, prometon, and prometryn. The ECOSAR

- estimated toxicity values indicate that GS

- 17794 is less toxic than parent ametryn to all taxa evaluated. Therefore, GS

- 17794 will not be considered a stressor of concern in the Registration Review ecologic al risk assessment.

### 23 Table 5 : ECOSAR

- predicted and Observed Toxicity Values for Ametryn and Major Degradates

T axon Exposure duration Toxicity Value (mg/L) Observed ECOSAR

- Predicted (Using ECOSAR Class Triazines) Ametryn GS

- 11354 GS

- 11355 NOA 423271

FW fi sh 96

- hr LC 50 Chronic value 3.6 0.7 8.55 0.24 58.5 1.5 3 124 3.18 4.63 0.1 3

SW fish 96

- hr LC 50 Chronic value 5.8 No data 9.26 0.91 43.0 0.67 78.2 3.92 5.7 0.65 Daphnid 48

- hr EC/LC 50 Chronic Value 28 0.24 9.37 0.37 34.3 1.44 56.5 2.4 5 6.25 0.24 Mysid shrimp 96

- hr LC 50 Chronic value 2.3 0.05 1.33 0.18 2.61 2.9 6 11.7 9.0 2 0.81 0.07 Green

a lgae 96

- hr EC 50 Chronic value 0.001 No data 0.05 0.04 0.12 0.0 7 0.18 0.0 9 0.04 0.03

Taxon Exposure duration Toxicity Value (mg/L) ECOSAR

- Predicted (Using ECOSAR Class Triazines) NOA 428383 NOA 438707 G 34048 GS

- 17794

FW fi sh 96

- hr LC 50 Chronic value 4.88e005 10858 11129 271 83.6 * 2.16 660 13. 8

SW fish 96

- hr LC 50 Chronic value 1.06e005 1439 4810 152 57.3 * 3. 2 261 9.0 2 Daphnid 48

- hr EC/LC 50 Chronic Value 39782 205 6 2758 127 43.7 * 1.8 7 156 7.11 Mysid shrimp 96

- hr LC 50 Chronic value 17100 4.17e005 738 192 9 8.5 * 4.9 6 39.7 81. 7 Green

a lgae 96

- hr EC 50 Chronic value 46.8 9.78 6.18 2.2 3 0.15 0.0 8 0.38 0.14 FW = freshwater; SW = saltwater * A sterisk designates that chemical may not be soluble enough to measure this predicted effect. If the effect level exceeds the water solubility by 10x, typically no effects at saturation (NES) are reported.

### 24 

## 4.2

**. Ecological Inci**  **dents**

The ecological incident information system (EIIS) is an OPP database that houses ecological incidents that have been reported to the Agency. When available, EIIS includes date and location of an incident, type and magnitude of effects observed in various species, use(s) of pesticides known or suspected of contributing to the incident, and results of any chemical residue analysis or other analyses conducted during incident investigation. EIIS incidents are categorized according to the certainty tha t the incident resulted from pesticide exposure. The Avian Monitoring System (AIMS) 11 

### is a database administered by the American Bird Conservancy that contains publicly available data on reported avian incidents involving pesticides. Many of the incidents listed in this database are also in the EIIS

. EIIS returned no major incidents. AIMS was also searched on December 5, 2012 and revealed no incidents to birds associated with ametryn

.

In the Aggregate Incident Reports there were no incidents attribute d to ametryn ( Appendix C )

. Because of uncertainties regarding the extent to which incidents are reported to EPA, the absence of incident reports cannot be construed as the absence of incidents

. During the risk assessment associated with Registration Revi ew of ametryn , these databases will be checked again and any new incidents will be evaluated to determine if the y represent current use patterns of ametryn

.



# 5. Exposure Pathways of Concern

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

The environmental fate properties of ametryn indicate the following transport mechanisms for potential exposure to aquat ic and terrestrial organisms:

• Direct contact

• Spray drift

• Runoff

• Consumption of contaminated food (sprayed food or treated seeds)

• Consumption of contaminated water

• Root uptake (plants)

11 http://www.abcbirds.org/abcprograms/policy/toxins/aims/aims/login.cfm

### 25 For terrestrial invertebrates, the major routes of exposure to ametry n are considered to be direct contact as a result of direct application and spray drift and dietary ingestion of plants, animals, and/or soil that have ametryn residues as a result of direct application, spray drift, and runoff.

For aquatic animal speci es, the major route of exposure to ametryn is considered to be uptake via the respiratory surface (gills) or the integument from surface water/sediment that has ametryn residues as a result of spray drift and runoff.

For terrestrial (upland and semi

- aquat ic) non

- target plants, the major routes of exposure to ametryn are considered to be direct contact as a result of direct application and spray drift and root uptake via soil contaminated via spray drift and runoff.

For aquatic plants, the major routes of exposure to ametryn are considered to be uptake from surface water/sediment containing ametryn residues as a result of spray drift, runoff, and leaching to groundwater from soil.

Drinking water and inhalation exposure pathways were screened using the SIP (Screening Imbibition Program) and STIR (Screening Tool for Inhalational Risk) programs. SIP results showed chronic exposure to the ametryn through drinking water represent s a potential concern for mammals and birds ( LOC exceedances expected) ( Appendix D )

. STIR found ametryn inhalation exposures to not likely be significant to avian species and mammals (no LOC exceedances are expected via this potential route of exposure) ( Appendix E ) . SIP and STIR are described in detail at: http://www.epa.gov/oppefed1/models/terrestrial/index.htm

.



# 6

. Analysis Plan

In order to address the risk hypothesis, the potential for adverse effects on the environment is estimated. The use, environmental fate, and ecological effects of ametryn are characterized and integrated to assess the risks. This is accomplished using a risk quotient (ratio of exposure concentration to effects concentration) approach. Although risk is often defined as the likelihood and magnitude of adverse ecological effects, the risk quotient

- based approach does not provide a quantitative estimate of l ikelihood and/or magnitude of an adverse effect. However, as outlined in the Overview Document (USEPA 2004), the likelihood of effects to individual organisms from particular uses of ametryn is estimated using the probit dose

- response slope and either the level of concern (discussed below) or actual calculated risk quotient value.

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

a metryn

. 

## 6.1. **Stressors of Concern**

### 26 Ecological Risk Assessment

Comparative toxicity modeling conducted in Section 4 indicates that the ametryn degradate NOA 423271 (ametryn sulfoxide) is potentially as toxic as parent ametryn to aquatic organisms. Additionally, both NOA 423271 and NOA 428383 are formed by aerobic soil metabolism, but may be reduced back to the parent form under certain environmental conditions. In the absence of data on the toxicity of NOA 423271 and NOA 428383 , the conservative method of considering the stressors of concern in total, i.e. , the total toxic residue (TTR) approach will be used. Therefore, these two degradates will be included as residues of concern for modeling aquatic exposure estimates for ecological risk assessm ent. For terrestrial assessments, exposure will be based on the parent compound alone since there is n o t a defined process for including specific degradates in terrestrial exposure estimates using the current model (TREX).

The stressors of concern are as follows:

• Terrestrial e nvironment: parent ametryn

• Aquatic e nvironment: parent ametryn , d egradate NOA 423271

, and d egradate NOA 428383

Th e decision whether to include unextracted residues in TTR estimates will be determined once the additional requested aerobic soil metabolism data have been reviewed as part of the Registration Review process.

Drinking Water

HED has determined that an updated drinking water assessment (DWA) is not needed to support f uture human health dietary risk assessments for ametryn.



## 6.2. **Measures of Exposure**

EFED will use standard available models (identified in Table 6 ) to evaluate potential exposures to aquatic and terrestrial organisms as described at http://www.epa.gov/pesticides/science/models_db.htm

. Aquatic exposure estimates will be based on estimated environmental concentrations ( EECs ) in a waterbody that is considered vulnerable and representative of static ponds and low

- order streams

. Terrestrial exposure will be estimated using a model (TREX ; version 1.5 ) that assumes direct application to a variety of avian, mammalian and reptilian food items. Exposure to terrestria l plants will be estimated using a model (TerrPlant version 1.2 ) that assumes ametryn drifts or moves with runoff to adjacent habitats. For more information on the various models that will be used in the risk assessment see the links as outlined in Table 6

.

### 27 Two spray drift models, AgD ISP and AgDRIFT, are used to assess exposures of aquatic and terrestrial organisms to ametryn deposited in terrestrial and aquatic habitats by spr ay drift. AgDRIFT ( version 2.1.1; dated 03/07/2012) is the model most commonly used to simulate spray drift into terrestrial and aquatic environments. A g D ISP ( version 8.26 ; dated 03/07/2012 ) is u sed when a parameter needs to be modeled tha t is not available in AgDRIFT. Spray drift analysis will be an important part of the analysis in defining the potential area of effects for endangered species.

A “ downstream dilution ” model (under development) may be used to identify water s downstream from a use area that may have EECs high enough to result in a risk concern. Such an analysis w ould be used to define potential area s of effects for listed species.

Table 6

. List of the various models and the related taxa for which the models will be used.

Environment Taxa of Concern Model (s) Link

Aquatic Fish/ Invertebrates /Plants PRZM/EXAMS http://www.epa.gov/oppefed1/models/ water/

Terrestrial Vertebrate TREX (dietary item) http://www.epa.gov/oppefed1/models/t errestrial/trex/trex_v1_5_webversion.xl

sm AGDISP (Spray drift) http://www.continuum

dynamics.com/pr

- agdisp.html

Plant TerrPlant (Run

- off) http://www.epa.gov/oppefed1/models/t errestrial/index.htm#terrplant AgDRIFT (Spray drift) http://www.agdrift.com/AgDRIFt2/Do wnloadAgDrift2_0.htm AGDISP (Spray drift) http://www.continuum

dynamics.com/pr

- agdisp.html



## 6.3. **Measures of Effect**

Toxicity data presented in Section 4 of this problem formulation will be used to calculate risk quotients. Any additional information submitted by the registrant or found in the open literature prior to conduct of the risk assessment will also be considered. The open literature studies ar e identified using EPA’s ECOTOXicology database ( ECOTOX) ( USEPA 2007 ), which employs a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, and wildlife. The evaluation of both sources of data can also provide insight into the direct and indirect effects of pesticides on biotic communities from loss of species that are sensitive to the chemical s and from changes in structure and functional characteristic s of the affected communities.

### 28 

## 6.4. **Endangered Species As sessments** 

Consistent with its responsibility under the Endangered Species Act (ESA), the Agency will evaluate risks to listed species from registered uses of ametryn

. These assessments will be conducted in accordance with standard EPA procedures and best professional judgment. The process for evaluating potential risks to listed species is further described in the Overview Document (USEPA 2004) at http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm

. The assessment of effects associated with registrations of ametryn is based on an action area. The action area is considered to be the area directly or indirectly affected by the federal act ion, as indicated by the exceedance of Agency LOCs used to evaluate direct or indirect effects. The Agency’s approach to defining the action area under the provisions of the Overview Document (USEPA 2004) considers the results of the risk assessment
proce ss to establish boundaries for that action area with the understanding that exposures below the Agency’s defined LOCs constitute a no

- effect threshold. For the purposes of this assessment, attention will be focused on the footprint of the action ( i.e. , th e area where ametryn application occurs), plus all areas where offsite transport ( i.e. , spray drift, runoff, etc .) may result in potential exposure that exceeds the Agency’s LOCs. Specific measures of ecological effect that define the action area for list ed species include any direct and indirect effects and/or potential modification of its critical habitat, including reduction in survival, growth, and reproduction as well as the full suite of sublethal effects available in the effects literature. Therefo re, the action area extends to a point where environmental exposures are below any measured lethal or sublethal effect threshold for any biological entity at the whole organism, organ, tissue, and cellular level of organization. In situations where it is not possible to determine the threshold for an observed effect, the action area is not spatially limited and is assumed to be the entire United States.



## 6.5. **Endocrine Disruptor Screening Program (EDSP)**

As required by FIFRA and FFDCA, EPA reviews numero us studies to assess potential adverse outcomes from exposure to chemicals. Collectively, these studies include acute, subchronic and chronic toxicity, including assessments of carcinogenicity, neurotoxicity, developmental, reproductive, and general or sy stemic toxicity. These studies include endpoints which may be susceptible to endocrine influence, including effects on endocrine target organ histopathology, organ weights, estrus cyclicity, sexual maturation, fertility, pregnancy rates, reproductive loss, and sex ratios in offspring. For ecological hazard assessments, EPA evaluates acute tests and chronic studies that assess growth, developmental and reproductive effects in different taxonomic groups. As part of its reregistration decision, EPA reviewed these data and selected the most sensitive endpoints for relevant risk assessment scenarios from the existing hazard database. However, as required by FFDCA section 408(p), ametryn is subject to the endocrine screening part of the Endocrine Disruptor Scre ening Program (EDSP).

### 29 EPA has developed the 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 of a battery of 11 screening assays to identify the potential of a chemical substance to interact with the estrogen, androgen, or thyroid (E, A, or T) hormonal systems. 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 E PA 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 effects caused by the substance, and establish a dose

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

Under Federal Food Drug and Cosmetic Act ( FFDCA ) section 408(p), the Agency must screen all pesticide chemicals for potential endocrine disruptor activity . 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 ingred ients and 9 inert ingredients. Ametryn is not among the group of 58 pesticide active ingredients on the initial list to be screened under the EDSP. Accordingly, as par t of R egistration R eview, EPA will issue future EDSP orders/data call

- ins, requiring the submission of EDSP screening assays for ametryn

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

. 

# 7. Preliminary Identification of Data Gaps

Several environmental effects and ecological effects studies o n ametryn are needed to better assess the potential risk of ex posure to non

- target organisms. Table s 1, 3 , and 4 summarize d data that have been submitted for the parent compound. The following studies are recommended to reduce uncertainty in risk estimation and characterization of ametryn.



## 7

**. 1** 

**. Environmental Fate** 

Tab le 7 identifies environmental fate studies by Master Record Identif i cation ( MRID ) number that provide data for each guideline requirement, as well as study clas sifications and whether or not further data are needed in order to support risk assessment. For the parent compound, data are needed for :

• aqueous photolysis (OCSPP Guideline 835.2 240 )

,

• aerobic soil metabolism (OCSPP Guideline 835.4100) , and

• aerobic aqu atic metabolism (OCSPP Guideline 835.4300)

.

### 30 The submitted aqueous photolysis study ( MRID 41169601; reclassified as not acceptable) failed to adequately show whether photodegradation was occurring, the rate of degradation, and which photodegradates might be formed. While the soil photodegradation study had similar deficiencies, the data for that study d id indicate that photodegradation on soil would not be a significant fate pathway

, thus new data are not likely to provide additional useful information for risk assessment . Additional aerobic soil metabolism data on three soils representative of the inte nded use areas are necessary to meet current data requirements. Analysis for the transformation products NOA 423271, NOA 428383, and NOA 438707, which were not tested for in previously submitted studies, should be included. Aerobic aquatic metabolism dat a for two sediment/water systems are required. In the past, a default of two times the aerobic soil metabolism half

- life was used for modeling. However, this is an inadequate estimate of metabolism rates in an aquatic environment where the parent may ref orm from NOA 423271 and NOA 428383, which are oxidized forms of ametryn that may be reduced back to parent in environmental conditions where the redox potential is below

- 148 mV. The level at which these degradates may form is uncertain, as they were not m onitored in all of the submitted metabolism studies.

Table 7 . Submitted Environmental Fate Data for Ametryn

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct risk assessment? Justification and Assumptions EPA will Make in Absence of Data

835.2120 Hydrolysis 40995812 Acceptable No Not applicable

835.2240 Aqueous photolysis 41169601 Not acceptable (reclassified) Yes Data are needed for modeling input and to clarify which transformation products may form /transform in water.

835.2410 Soil photolysis 41169602 & 41169603 Not acceptable (reclassified) No Because the half

- lives in the irradiated soils were near or greater than 100 days, the stability of a metryn to photodegradation on soil will be assumed for the fate characterization. Soil photolysis is expected to be less of a significant fate pathway for ametryn than aerobic soil metabolism. Photodegradation in air Waived

-- No Not applicable

835.4100 Aerobic soil metabolism 41752401 Acceptable

Yes Data are required for 3 additional soils representative of intended use areas. The transformation products NOA 423271, NOA 428383, and NOA 438707 should be included in the monitoring along with other potential transformation products

. 46533801 Supplemental

255735 Not acceptable

835.4200 Anaerobic soil metabolism 41752401 Acceptable
No Not applicable 46533801 Supplemental

255735 Not acceptable

### 31 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct risk assessment? Justification and Assumptions EPA will Make in Absence of Data

835.4300 Aerobic aquatic metabolism No data

-- Yes EPA will assume stability in the absence of data. The use of 2X the aerobic soil metabolism half

- life as a default input value in lieu of data will likely overestimate any potential degradation in an aquatic environment where the parent may reform from NOA 423271 and NOA 428383, which are oxidized forms of ametryn that may be reduced back to parent in environmental conditions where the redox potential is below

- 148 mV.

835.4400 Anaerobic aquatic metabolism 46533801 Supplemental

No Not applicable

42861603 Acceptable

835.1230 835.1240 Adsorption/ desorption and leaching 41169604 Acceptable

No

_ 41169605 Supplemental

40995813 Acceptable

835.1410 Volatility laboratory Waived

-- No Not applicable
Field volatility Waived

-- No Not applicable

835.6100 Terrestrial field dissipation 41872301 41872302 41752402 Supplemental No TFD data requirement was waived in 1991 in favor of a small

- scale prospective groundwater study.
G roundwater Monitoring 45629801 45870401 Not Classified Not at this time.

_ Droplet Size Spectrum 41336801 Acceptable No Not Applicable

Drift field evaluation 41336802 41268001 Not Acceptable No Spray Drift Task Force data are used for this data requirement.

835.6100 Environ mental chemistry method in soil and sediment and water and associated ILV No MRID (Report No. ECM0063Sl

S4) Acceptable No Not Applicable

8 50 .6100 Environmental chemistry method in water and associated ILV No data

-- Yes

--

### 32 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct risk assessment? Justification and Assumptions EPA will Make in Absence of Data

850.1730 Fish bioconcentration 42061901 Acceptable No Based on study results and a K ow of 4.3 X 10 2 (log K ow = 2.6), ametryn residues are not expected to bioconcentrate in fish to a significant extent.



## 7. **2**

**. Ecological Effects** 

One ecological effects study on ametryn is needed to better assess the potential risk of exposure to non

- target organisms. Tables 3 and 4 summarize d data that have been submitted for the parent compound. The following studies are recommended to reduce uncertainty in risk estimation and charact erization of ametryn:

• Algal and Cyanobacteria ( Anabaena flos

- aqua ) Toxicity

– (guidelines 850.4500 and 850.4550 ) [3 Studies] Data for aquatic non

- vascular plant species are required under 40 CFR Part 158. No studies have been submitted for a freshwater diatom ( e.g. , Navicula pelliculosa ), a marine diatom ( e.g. , Skeletonema costatum ), or a cyanobacterium ( e.g., Anabaena flos

- aqua ). Given that the 2005 RED (DP 316704 ) identified a risk concern for aquatic non

- vascular plants, fulfilling this data requirement has a high potential to add value to the Registration Review risk assessment.

Table 8 and 9 identify ecological effects studies by MRID that provide data for each guideline requirement, as well as study classifications and whether or not additional data are needed in order to support risk assessment.

Table 8 . Submitted Aquatic Ecological Effects Data for Ametryn

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct

risk assessment? Justification and Assumptions EPA will

Make in Absence of Data

850.1010 Freshwater invertebrate acute toxicity 409958 06 Acceptable No

--

850.1025 850.1035 Saltwater invertebrate acute toxicity 411149 01 Acceptable No

-- 411149 03

, 423252 01 Acceptable

850.1075 Freshwater fish acute toxicity 42861601 Acceptable

No

-- 428616 02 Acceptable

409958 04 Supplemental

409958 05 Supplemental

00116257 Acceptable

### 33 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct

risk assessment? Justification and Assumptions EPA will

Make in Absence of Data

00033309 Supplemental

00033706 Acceptable

850.1075 Saltwater fish acute toxicity 411149 02 Acceptable No

--

850.1300 Freshwater invertebrate

life cycle 41189702, 423252 02 Supplemental No The study was classified

as supplemental due to no statistically significance difference in length between the solvent control and any of the
treatments. However, data can still be used for risk assessment.

850.1350 Saltwater invertebrate

life cycle 47399001 Acceptable No

850.1400 Freshwater fish early

- life

stage 411897 03, 4232520 3 Acceptable No

--

850.1400 Saltwater fish early

- life

stage Waiver request granted -- No

--

850.1500 Fish life cycle No Data

-- No A lthough fish full life

cycle testing is currently required under 40 CFR Part 158, chronic toxicity data are available for ametryn through a fish early life stage study that has been classified as acceptable. Therefore data for this study is not required at this time.

850.4400 Aquatic plant growth: Tier II vascular

plants 473990 02 Acceptable No

--

850.4500 Aquatic Plant Growth: 40995810 (Green Algae) Acceptable No

--

### 34 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed to conduct

risk assessment? Justification and Assumptions EPA will

Make in Absence of Data

Tier II algae No data for freshwater

diatom -- Yes D ata for aquatic non

vascular plant species including a freshwater diatom are required under 40 CFR Part 158.

No data for marine diatiom -- Yes D ata for aquatic non

vascular plant species including a marine diatom are required under 40 CFR Part 158.

850.4550 Aquatic Plant Growth (aquatic non

vascular

plant: cyanobacteria toxicity) No data

-- Yes D ata for aquatic non

v ascular plant species including a cyanobacterium are required under 40 CFR Part 158.



### Table 9 . Submitted Terrestrial Ecological Effects Data for Ametryn

OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed for risk assessment? Justification and Assumptions EPA will Make in Absence of Data

850.2100 Avian oral toxicity ( upland game bird ) 40995801 Acceptable No

--

Avian oral

toxicity ( passerine ) No data

-- No W hile passerine testing is now required under 40 CFR Part 158, available data indicate that ametryn is practically nontoxic to birds on an acute oral and subacute dietary exposure basis and there are no incident data to indicate that passerine testing should be required at this time

.

850.2200 Avian dietary toxicity 409958 02 Acceptable

No

-- 4 09958 03 Acceptable

00080617 Acceptable

00115791 Acceptable

850.2300 Avian reproduction 415476 02 Acceptable No

-- 41547 6 01 Acceptable

### 35 OCSPP Guideline Data Requirement Submitted Studies (MRID) Study Classifications Are data needed for risk assessment? Justification and Assumptions EPA will Make in Absence of Data

850.3020 Honey bee
acute contact toxicity 409958 11 Acceptable No

--

850.4100 Seedling
emergence and seedling growth 40995808 Acceptable No

--

850.4150 Vegetative vigor 40995809 Acceptable No

--



# 8

. References

Davis, A., S. Lewis, Z. Bainbridge, J. Brodie and E. Shannon. 2008. Pesticide Residues in Waterways of The Lower Burdekin Region: Challenges in Ecotoxicological Interpretation of Monitoring Data. Australasian Journal of Ecotoxicology Vol. 14, Pp. 89

- 108, 2008.

Food and Agriculture Organization of the United Nations . 2000. FAO PESTICIDE DISPOSAL SERIES 8. Assessing Soil Contamination: A Reference Manual. Appendix 2. Parameters of pesticides that influence processes in the soil. Editorial Group, FAO Information Division. Rome.

Goring, C.A.I., D.A. Laskowki, J.H. Ham aker, and R.W. Meikle. 1975. Principles of pesticide degradation in soil. Pages 135

- 172 in (R. Haque and V.H. Freed, eds.) Environmental dynamics of pesticides . Plenum Press, New York.

SFWMD, 2009. Pesticide Surface Water and Sediment Quality Report Marc h 2008 Sampling Event . South Florida Water Management District. August 2009.

SFWMD, 2012. Pesticide Surface Water Quality Report March 2011 Sampling Event

. South Florida Water Management District. 2012.

Sposito, G. 1989. The Chemistry of Soils. 277 pp. New York, Oxford: Oxford University Press.

USEPA. 2004. Overview of the Ecological Risk Assessment Process in the Office of Pesticide Programs . United States Environmental Protection Agency (USEPA). Environmental Fate and Effects Division. Office o f Pesticide Programs. Available at http://www.epa.gov/espp/consultation/ecorisk

- overview.pdf (Accessed January 7, 2013 ).

### 36 USEPA. 2005a. Drinking Water Exposure Assessment for Proposed Reregistration of Ametryn Use on Corn, Pineapple and Sugarcane (Revised). DP Barcode 307097. United States Environmental Protection Agency (USEPA). Environmental Fate and Effects Division. Office of Pesticide Programs. May 2005.

USEPA. 2005b. Environmental Fate and Ecological Risk Assessment for the Re

registration of Ametryn . DP Barcode 316704. United States Environmental Protection Agency (USEPA). Environmental Fate and Effects Division. Office of Pesticide Programs. June 2005.

USEPA. 2005 c

. PRZM 3.12.2: Users Manual. Online at: http://www.epa.gov/oppefed1/models/water/#przm

US EPA. 2005 d . EXAMS 2.98.04.06: Users Manual. Online at: http://www.epa.gov/oppefed1/models/water/#exams

US EPA. 2006. Water models PE Version 5: User Manual. Online at: http://www.epa.gov/oppefed1/models/water/pe5_ user_manual.htm

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

USEPA. 2012. BEAD Chemical Profile for Registration Review: Ametryn (080801 )

. Memorandum From S. Ratnayake, S. Haddad, and A. Lee to Molly Clayton. Biological and Economic Analysis Division to Pesticide Reevaluation Division. March 21, 2012.

USFWS/NMFS. 1998. Endangered Species Consultation Handbook: Procedures for Conducting Consultation and Confere nce Activities Under Section 7 of the Endangered Species Act. Final Draft. United States Fish and Wildlife Service (USFWS) and National Marine Fisheries Service (NMFS). Available at : http://www.fws.gov/endangered/consultations/s7hndbk/s7hndbk.htm

### 37 

# 9. Appendices

Appendix A. Submitted Environmental Fate and Effects Studies

SUBMITTED FATE STUDIE S (as of 2/6 /1 3 )

Hydrolysis

23963 Burkhard, N. (1976) Project Report 17/76: Hydrolysis of 2

- Chloro

- and 2

- Methylthio

- 4,6

- bis

- (alkylamino)

- s

- triazines under Laboratory Conditions. (Unpublished study received Apr 27, 1977 under 100

- 588; prepared by Ciba

- Geigy, Ltd., submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:229641

- A)

24 013 Pape, B.E.; Zabik, M.J. (1970) Photochemistry of bioactive compounds: Photochemistry of selected 2

- Chloro

- and 2

- Methylthio

- 4,6

- di

- (alkylamino)

- s

- triazine herbicides. Journal of Agricultural and Food Chemistry 18(2):202

- 207. (Also in unpublished submi ssion received Aug 28, 1975 under 100

- 437; submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:221042

- N)

24328 Burkhard, N.; Guth, J.A. (1976) Photodegradation of Atrazine, Atraton and Ametryne in aqueous solution with Acetone as a photosensitiser. Pesti cide Science 7(1):65

- 71. (Also in unpublished submission received Jul 19, 1978 under 201

- 403; submitted by Shell Chemical Co., Washington, D.C.; CDL:234469

- C)

24329 Ruzo, L.O.; Zabik, M.J.; Schuetz, R.D. (1973) Photochemistry of bioactive compounds. Kinetics of selected s

- Triazine in solution. Journal of Agricultural and Food Chemistry 21 (6):1047

- 1049. (Also in unpublished submission received Jul 19, 1978 under 201

- 403; submitted by Shell Chemical Co., Washington, D.C.; CDL:234469

- D)

27855 Burkhard , N. (1976) Hydrolysis of 2

- Chloro

- and 2

- Methylthio

- 4,6

- bis

- (alkylamino

- striazines under Laboratory conditions: Project Report 17/76. (Unpublished study received Jul 17, 1978 un

- der 100

- 541; prepared by Ciba

- Geigy, Ltd., submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:234454

- A)

63054 Burkhard, N. (1976) Hydrolysis of 2

- Chloro

- and 2

- Methylthio

- 4,6

- bis

- (alkylamino)

- striazines under Laboratory Conditions: Proj

- ect Report 17/76. (Unpublished study received Nov 18, 1980 un

- der 40810

- 2; prepared by Ciba

- Geigy, Ltd., Switzerland, submit

- ted by Ciba

- Geigy Corp., Ardsley, N.Y.; CDL:243792

- D)

147564 Balu, K. (1984) Summary of Environmental Fate Studies Ametryn: Report No: EIR

- 84028. Unpublished study prepared by Ciba

- Geigy Corp. 13 p.

40995812 Spare, W. (1988) Hydrolysis of carbon 14|

- Ametryn: Final Report: Project No. 12135. Unpublished study prepared by Agrisearch Inc. 94 p.

92002035 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995812. Ametryn

Hydrolysis Study: Project 12135. Prepa red by AGRISEARCH, INC. 11 p. Bibliography Page 29 of 66

161

- 2 Photodegradation in water

146397 Halama, P.; Balu, K.; Hofberg, A. (1972) Photolysis of Ametryne in Aqueous Solution under Natural and Artificial Sunlight Condi

- tions: Report No: GAAC

- 7211 7. Unpublished

### 38 study prepared by Ciba

- Geigy Corp. 14 p.

147564 Balu, K. (1984) Summary of Environmental Fate Studies Ametryn: Report No: EIR

- 84028. Unpublished study prepared by Ciba

- Geigy Corp. 13 p.

41169601 Spare, W. (1989) Aqueous Photolysis of ?carbon 14|

- Ametryn: Final Report: Study No. 12136. Unpublished study prepared by Agri

- search Inc. 125 p.

92002036 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41169601. Ametryn

Aqueous Photolysis Study: Project 12136. Prepared by AGRISEA RCH, INC. 16 p.

161

- 3 Photodegradation on soil

146398 Burkhard, N. (1979) Photolysis of Ametryn (Gesapax) on Soil Sur

- faces under Artificial Sunlight Conditions: Project Report 07/ 79. Unpublished study prepared by Ciba

- Geigy Ltd. 10 p.

147564 Balu, K. (1984) Summary of Environmental Fate Studies Ametryn: Report No: EIR

- 84028. Unpublished study prepared by Ciba

- Geigy Corp. 13 p.

41169602 Spare, W. (1989) Soil Photolysis of Ametryn by Natural Sunlight at Vero Beach, Florida:Final Report: Study No. 12137 . Unpublished study prepared by Arisearch Inc. 85 p.

41169603 Spare, W. (1989) Soil Photolysis of Ametryn by Natural Sunlight and Artificial Light: Final Report: Study No. 12137. Unpublished study prepared by Agrisearch Inc. 141 p.

92002037 Hochman, J. ( 1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41169603 and Related MRIDs 41169602. Ametryn

- Soil Photolysis Study: Project 12137. Prepared by AGRISEARCH, INC. 14 p.

162

- 1 Aerobic soil metabolism

146397 Halama, P.; Balu, K.; Hofberg, A. (1972) Photolysis of Ametryne in Aqueous Solution under Natural and Artificial Sunlight Condi

- tions: Report No: GAAC

- 72117. Unpublished study prepared by Ciba

- Geigy Corp. 14 p.

147564 Balu, K. (1984) Summary of Environmental Fate Studies Ametryn: Report No: EIR

- 84028. Unpublished study prepared by Ciba

- Geigy Corp. 13 p.

41169601 Spare, W. (1989) Aqueous Photolysis of ?carbon 14|

- Ametryn: Final Report: Study No. 12136. Unpublished study prepared by Agri

- search Inc. 125 p. 92002036 Hochman, J. (1990) Ciba

- Geigy Corp. Ph ase 3 Summary of MRID 41169601. Ametryn

Aqueous Photolysis Study: Project 12136. Prepared by AGRISEARCH, INC. 16 p.

146398 Burkhard, N. (1979) Photolysis of Ametryn (Gesapax) on Soil Sur

- faces under Artificial Sunlight Conditions: Project Report 07/ 79. Unpublished study prepared by Ciba

- Geigy Ltd. 10 p.

147564 Balu, K. (1984) Summary of Environmental Fate Studies Ametryn: Report No: EIR

- 84028. Unpublished study prepared by Ciba

- Geigy Corp. 13 p.

41169602 Spare, W. (1989) Soil Photolysis of Ametryn by Natural Sunlight at Vero Beach, Florida: Final Report: Study No. 12137. Unpublished study prepared by Arisearch Inc. 85 p.

41169603 Spare, W. (1989) Soil Photolysis of Ametryn by Natural Sunlight and Artificial Light: Final Report: Study No. 12137. Unpubl ished study prepared by Agrisearch Inc. 141 p.

### 39 92002037 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41169603 and Related MRIDs 41169602. Ametryn

- Soil Photolysis Study: Project 12137. Prepared by AGRISEARCH, INC. 14 p.

146399 Ercegovich, C .; Bogus, E. (1975) The Fate of 2

- Ethylamino

- 4

- isopropylamino

- 6

- methylthio

- s

- triazine (Ametryn) in Hagerstown Silt Loam Soil Maintained under Aerobic and Anaerobic Conditions: Report E

- 6/5

- 75CG. Unpublished study prepared by Pennsylvania State University. 41 p.

41752401 Spare, W. (1990) Ametryn: Aerobic and Anaerobic Soil Metabolism of ?Carbon 14|

- Ametryn: Lab Project Number: 12138. Unpublished study prepared by Agrisearch Inc. 166
p.

43407105 Burnett, G. (1994) Response To The United States Environmental Protection Agency Bibliography Page 30 of 66

162

- 2 Anaerobic soil metabolism

146399 Ercegovich, C.; Bogus, E. (1975) The Fate of 2

- Ethylamino

- 4

- isopropylamino

- 6

- methylthio

- s

- triazine (Ametryn) in Hagerstown Silt Loam Soil Maintained under Aerobic and Anaerobic Conditions: Report E

- 6/5

- 75CG. Unpublished study prepared by Pennsylvania State University. 41 p.

41752401 Spare, W. (1990) Ametryn: Aerobic and Anaerobic Soil Metabolism of ?Carbon 14|

- Ametryn: Lab Project Number: 12138. Unpublish ed study prepared by Agrisearch Inc. 166
p.

162

- 3 Anaerobic aquatic metabolism

42861603 Skinner, W. (1993) Anaerobic Aquatic Metabolism of (Carbon 14) Ametryn: Lab Project Number: 354W: 171

- 91. Unpublished study prepared by PTRL

- West, Inc. 167 p.

163

- 1 Leaching/adsorption/desorption

. 23700 Suzuki, H.K. (1979) Dissipation of Banvel or Banvel in Combination with Other Herbicides: Two Soil Types: Report No. 197. (Unpub

- lished study received Mar 5, 1979 under 876

- 25; prepared in co

- operation with Craven Laboratories, Inc., submitted by Velsicol Chemical Corp., Chicago, Ill.; CDL:241224

- B)

24365 Jordan, L.S.; Day, B.E.; Clerx, W.A. (1964) Photodecomposition of Triazines. Weeds 12 (? ):5

- 6. (Also~In~unpublished submission received Jul 19, 1978 under 201

- 40 3; submitted by Shell Chemical Co., Washington, D.C.; CDL:234470

- G)

27128 Rodgers, E.G. (1968) Leaching of seven s

- Triazines. Weed Science 16(? ):117

- 120. (Also in unpublished submission received Jul 19, 1978 under 201

- 403; submitted by Shell Chemical Co., Washington, D.C.; CDL:234472

- B)

38374 Guth, J.A. (1972) Adsorption and Leaching Characteristics of Pesticides in Soil. A translation of: Adsorptions

- und Einwaschverhalten von Pflanzenschutzmitteln in Boeden. (Unpublished study including German text, received Jul 19, 1978 under 201

- 403; prepared by Ciba

- Geigy, AG, submitted by Shell Chemical Co., Washington, D.C.; CDL:234472

- S)

143342 Hazleton Laboratories America, Inc. (1985) The Absorption

- desorp

- tion of Radiolabelled Ametryn on Representative Ag ricultural Soils: Study No. 6015

- 158. Unpublished study. 45 Bibliography Page 31 of 66

### 40 158732 Liu, L.; Cibes

- Viade, H.; Koo, F. (1970) Adsorption of ametryne and diuron by soils. Weed Science 18(4):470

- 474.

5016652 Helling, C.S. (1971) Pesticide mobility in soils: II_ Applications of soil thin

- layer chromatography. Proceedings of the Soil Science Society of America 35(5):737

- 743.

40079901 Warren, J. (1986) Leaching Characteristics of Parent [Carbon 14]

- Ametryn: Final Report: Laboratory Study No. 34998. Unpublished study prepared by Analytical Bio

- Chemistry Laboratories, Inc. 144 p.

40995813 Spare, W. (1988) Adsorption/Desorption of ?carbon 14|

- Ametryn: Final Report: Project No. 12141. Unpublished study prepared by Agrisearch, Inc. 100 p.

41169604 Spare , W. (1989) Leaching Characteristics of ?carbon 14|

- Ametryn: Final Report: Study No. 12139. Unpublished study prepared by Agrisearch Inc. 81 p.

41169605 Spare, W. (1989) Leaching Characteristics of Aged Ametryn: Final Report: Study No. 12140. Unpublished study prepared by Agri

- search Inc. 71 p.

41189704 Spare, W. (1988) Adsorption/Desorption of ?carbon|

- Ametryn: Final Report: Study No. Agrisearch Project No. 12141. Unpublished study prepared by Agrisearch Inc. 100 p.

43407105 Burnett, G. (1994) Response To The United States Environmental Protection Agency Review Of The Prometryn Environmental Fate Data: Lab Project Number: ABR

- 94079. Unpublished study prepared by Ciba Crop Protection. 54 p.

92002038 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995813. Ametryn

- Adsorption/Desorption: Project 12141. Prepared by Agrisearch Inc. 11 p.

92002045 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41169605. Ametryn

- Aged Leaching Characteristics: Project No. 12140. Prepared by AGRISEA RCH, INC. 14 p.

92002046 Hochman, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41169604. Ametryn

- Leaching Characteristics: Project 12139. Prepared by AGRISEARCH, INC. 12 p.

164

- 1 Terrestrial field dissipation

15644 Suzuki, H.K.; Takado, D.Y.; Whi tacre, D.M. (1979) Laboratory Report: Dissipation of Banvel or Banvel in Combination with Other Herbicides: Two Soil Types: Report No. 197. (Unpublished study received Mar 5, 1979 under 876

- 25; prepared in cooperation with Craven Laboratories, Inc., submit ted by Velsicol Chemical Corp., Chicago, Ill.; CDL:237957

- I)

17711 Liu, L.C.; Cibes

- Viade, H.R.; Gonzalez

- Ibanez, J. (19??) Persistence of several herbicides in a soil cropped to sugarcane. Journal of Agriculture of University of Puerto Rico ? (? ):147

- 1 52. (Also In unpublished submission received Aug 20, 1976 under 39445

- 1; submitted by American Carbonyl, Inc., Tenafly, N.J.; CDL:228229

- Y)

38292 Maier

- Bode, H. (1972) Behavior of Herbicides in Water, Muck, and Fish after Application in Fish Ponds. A tran slation of: Verhalten von Herbiziden in Wasser, Schlamm und Fischen nach Applikation in Fischteichen. (Unpublished study including German text, received Jul 19, 1978 under 201

- 403; submitted by Shell Chemical Co., Washington, D.C.; CDL:234470

- K)

### 41 115781 Geigy Chemical Corp. (1972) Petition for a Negligible Residue Tolerance of 0.25 PPM in Grapefruit and Oranges for the Herbicide... Ametryne|. (Compilation; unpublished study received May 30, 1973 under 3F1299; CDL:092199

- A)

140127 Cassidy, J. (1971) Metab olism of ?delta|

- 14C

- ametryne in Soil and Mature Corn Silage and Grain: Report No.: GAAC

- 71032. (Unpublished study received 1971 under 3F1299; submitted by Ciba

- Geigy Corp., Greensboro, NC; CDL:098818

- B)

158995 Horowitz, M. (1969) Evaluation of herbicide persistence in soil. Weed Res. 9:314

- 321. 41701601 Judy, D.; Jacobson, B. (1990) Ametryn: Terrestrial Field Dissipation for Evik 80W

-- Bareground Application, Louisiana Site: Final Report: Lab Project Number: 37895. Unpublished study prepared by Analytica l Bio

- Chemistry Laboratories, Inc. 219 p.

41752402 Judy, D.; Jacobson, B.; Gresham M. (1991) Ametryn: Terrestrial Field Dissipation for Evik 80W

- Crop Application, Louisiana Site: Final Report: Lab Project Number: 37894. Unpublished study pre

- pared by Ana lytical Bio

- Chemistry Laboratories in assoc. with Pest Management Enterprises, Inc. 267 p.

41872301 Jacobson, B.; Gresham, M. (1991) Terrestrial Field Dissipation for Evik 80W

- Bareground Application, Illinois Site: Ametryn: Final Report: Lab Project Numbe r: 38184. Unpublished study prepared by ABC Laboratories, Inc., & Agri

- Research Associates, Inc. 247 p.

41872302 Rice, F.; Jacobson, B.; Gresham, M. (1991) Terrestrial Field Dissipation for Evik 80WCrop Application, Illinois Site: Ametryn: Final Report: L ab Project Number: 38183. Unpublished study prepared by ABC Laboratories, Inc., & Agri

- Research Asso

- ciation, Inc. 256 p.

42325204 Jacobson, B. ; Graham, M. (1991) Terrestrial Field Dissipation for Evik 80W

— Bareground Application, Hawaii Site (Ametryn, F inal Report): Lab Project Number: FR 37896. Unpublished study prepared by ABC Labs, Inc. 205 p.

165

- 4 Bioaccumulation in Fish

42061901 Dionne, E. (1991) Bioconcentration and Elimination of (Carbon 14) Residues by (Lepomis macrochirus) Exposed to Ametryn: Lab Project Number: 1781. 1090. 6264. 140: 91

- 5

- 3760: 155

- 90. Unpublished study prepared by Springborn Labs, Inc. and Ciba

- Geigy Corp. 156 p.

166

- 1 Small GW prospective

45629801 Yokley, R. (2002) FIFRA Section 6(a)(2) Annual Ground Water Report for 2001. Unpublished study prepared by HAES Resources Department, Syngenta Crop Protection, Inc. 33 p.

45870401 Yokley, R. (2003) FIFRA Section 6(a)2 Annual Ground Water Report for 2002:Final Report: Lab Project Number: 2240

- 02. Unpublished study prepared by Syngenta Crop Protection, Inc. 34 p.

Dawson, Jeffrey et al. "Evik 80W Droplet Size Spectrum Study'. Conducted by Agrisearch lncorporated for Ciba

- Geigy Corporation. Study completed on December 11, 1989 and received by EPA on December 26, 1989. MRlD #: 41 336801.

Merricks, D. Larry. "Evik 80W Aerial Spray Drift Study

- Louisiana Siten. Conducted by Agrisearch lncorporated for Ciba

- Geigy Corporation. Study completed on April 10, 1989 and received by EPA

### 42 on October 16, 1989. MRlD #: 41268001.

Merricks, D. La rry. "Evik 80W Aerial Spray Drift Study

- Hawaii Site". Conducted by Agrisearch Incorporated for Ciba

- Geigy Corporation. Study completed on October 11, 1989 and received by EPA on December 26, 1989. MRlD #: 41336802.



### S UBMITTED EFFECT STUDIES (as of 1/25/13 )

71

- 1 Avian Single Dose Oral Toxicity
MRID Citation Reference

56908 Ciba

- Geigy Corporation (1967) Toxicology: (Evik(R)). (Reports by various sources; unpublished study including IBT nos. B4715, C4716 and P4709, received Apr 14, 1971 under 1G1142; CDL: 090929

- B)

116260 Fink, R.; Beavers, J.; Brown, R. (1977) Acute Oral LD 50

-- Mallard Duck: Ametryn: Project No. 108

- 130. Final rept. (Unpublished study received Dec 29, 1977 under 100

- 579; prepared by Wildlife International, Ltd. and Washington College, submitted by Ciba

- Ge igy Corp., Greensboro, NC; CDL:232548

- I)

40995801 Grimes, J.; Jaber, M. (1988) Ametryn: An Acute Oral Toxicity Study with the Bobwhite: Final Report: Project No. 108

- 291. Unpu

- blished study prepared by Wildlife International Ltd. 20 p.

92002004 Plaut z, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995801. Acute Oral Toxicity of Ametryn Technical to Bobwhite Quail: Report No. 108

- 291. Prepared by Wildlife International LTD. 17 p.

71

- 2 Avian Dietary Toxicity
MRID Citation Reference

33704 or 80617 Beliles, R.P.; Woodard, G. (1964) Ametryne: Subacute Toxicity of Ametryne in Bobwhite Quail. (Unpublished study received on un

- known date under 100

- 473; prepared by Woodard Research Corp., submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CD L:000475

- B)

48236 Woodard Research Corporation (1949?) Ametryne: Subacute Toxicity in Mallard Ducks. (Unpublished study received Jul 23, 1965 un

- der unknown admin. no.; submitted by Ciba

- Geigy Corp., Greens

- boro, N.C.; CDL:222959

- B)

48238 Beliles, R. P.; Scott, W.; Knott, W.; et al. (1964?) Ametryne: Sum

- mary of Safety Evaluation on Fish and Wildlife. Summary of studies 222959

- A through 222959

- C. (Unpublished study received Jul 23, 1965 under unknown admin. no.; prepared by Woodard Re

- search Corp., s ubmitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:222959

- D)

80617 Beliles, R.P.; Woodard, G. (1964) Ametryne: Subacute Toxicity of Ametryne in Bobwhite Quail. (Unpublished study received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp.,

su bmitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- K)

80619 Beliles, R.P.; Scott, W.; Knott, W.; et al. (1949) Ametryne: Sub

- acute Toxicity in Mallard Ducks. (Unpublished study received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp., submitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- M)

80621 Beliles, R.P.; Scott, W.; Knott, W.; et al. (1964) Ametryne: Sum

- mary of Safety Evaluation on

### 43 Fish and Wildlife. Summary of studies 091109

- I through 091109

- N. (Unpublished study received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp., submitted by Geigy Chemical Corp., New York, N.Y .; CDL:091109

- O)

115791 Beliles, R.; Scott, W.; Knott, W. (1964) Ametryne Safety Evaluation in Fish and Wildlife (Final Report) (Rainbow Trout, Mallard Duck, Oysters). (Unpublished study received Aug 30, 1965 under unknown admin. no.; prepared by Woodard Research Corp., submitted by Ciba

- Geigy Corp., Greensboro, NC; CDL:129363

- A)

116261 Gough, B.; Shellenberger, T. (1972) Letter sent to J. Forsythe dated Jan 28, 1972: Acute and subacute toxicity feeding studies of ametryne with young adult bobwhite quai l: GSRI No. NC

- 459. (Unpublished study received Dec 29, 1977 under 100

- 579; prepared by Gulf South Research Institute, submitted by Ciba

- Geigy Corp., Greensboro, NC; CDL:232548

- J)

40995802 Grimes, J.; Jaber, M. (1988) Ametryn: A Dietary LC50 Study with t he Mallard: Project No. 108

- 290A. Unpublished study prepared by Wildlife International Ltd. 19 p.

40995803 Grimes, J.; Jaber, M. (1988) Ametryn: A Dietary LC50 Study with the Bobwhite: Project No. 108

- 289. Unpublished study prepared by Wildlife Internati onal Ltd. 18 p.

92002005 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995803. Acute Dietary Toxicity of Ametryn Technical to Bobwhite Quail: Report No. 108

- 289. Prepared by Wildlife International LTD. 16 p.

92002006 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995802. Acute Dietary Toxicity of Ametryn Technical in Mallard Duck: Report No. 108

- 290A. Prepared by WILDLIFE INTERNATIONAL LTD. 16 p.
71

- 4 Avian Reproduction
MRID Citation Reference

41547601 Beavers, J. (1990) Ametryn Technical: A One

- Generation Reproduction Study with the Northern Bobwhite (Colinus virginianus): Lab Pro

- ject Number: 108

- 303. Unpublished study prepared by Wildlife International Ltd. 116 p.

41547602 Beavers, J. (1990) Ametryn Technical: A One

- Generation Reproduction Study with the Mallard (Anas platryhyncos): Lab Project Number: 108

- 304. Unpublished study prepared by Wildlife International Ltd. 119 p.
72

- 1 Acute Toxicity to Freshwater Fish
MRI D Citation Reference

31150 or 33309 or 43665 Sleight, B.H., III (1971) Acute Toxicity of Some Ciba

- Geigy Experimental Chemicals to Fathead Minnows (Pimephales promelas). (Unpublished study received Jan 16, 1974 under 1F1154; prepared by Bionomics, Inc., submitted by Ciba

- Geigy Corp., Greensboro, N.C. ; CDL:092100

- W)

33308 Gast, A. (1963) Toxicity Experiments on Trout for Breeding. (Unpublished study including pp. 1

- 2 of appended German translation entitled: Toxizitaetsversuche an Brutforellen, received May 16, 1973 under 1769

- 234; submitted by NCH Corp., National Chemsearch Div., Irving, Tex.; CDL:221976

- E)

33309 or 43665 Sleight, B.H., III (1971) Bioassay Report: Acute Toxicity of Some Ciba

- Geigy Experimental Chemicals to Fathead Minnows (Pimephales promelas). (Unpublished study received May 16, 1973 under 1769

- 234; prepa red by Bionomics, Inc., submitted by NCH Corp., National Chemsearch Div., Irving, Tex.; CDL:221976

- N)

### 44 43665 Macek, K.J.; Sleight, B.H., III (1971) Bioassay Report: Acute Toxicity of Some Ciba

- Geigy Experimental Chemicals to Fathead Minnows (Pimephales pr omelas). (Unpublished study received Apr 27, 1977 under 100

- 541; prepared by Bionomics, Inc., submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:229607

- S)

80616 or 33705 Beliles, R.P.; Woodard, G. (1964) Ametryne: Acute Toxicity in Gold

- fish. (Unpubli shed study received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp., submitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- J)

80618 Beliles, R.P.; Scott, W.; Knott, W.; et al. (1964) Acute Toxicity in Rainbow Trout. (Unpublished
stu dy received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp., submitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- L)

80621 Beliles, R.P.; Scott, W.; Knott, W.; et al. (1964) Ametryne: Sum

- mary of Safety Evaluation on Fish and Wild life. Summary of studies 091109

- I through 091109

- N. (Unpublished study received Mar 27, 1967 under 8F0638; prepared by Woodard Research Corp., submitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- O)

80622 Lowe, J.I. (1964) Letter sent to H.E. Fa irchild dated Jul 28, 1964 (Acute aquatic toxicity tests: ametryn and other chemicals). (U.S. Fish and Wildlife Service, Bureau of Commercial Fisheries, Biological Laboratory; unpublished study, including Geigy Chemical Corp. CDL:091109

- P)

92511 Hughes, J.S. (1970) Letter sent to Aithel McMahon dated Feb 10, 1970 ?Toxicity of Princep 80W and Ametryne to bluegill and channel catfish|: 71201. (Louisiana, Wild Life and Fisheries Commission; unpublished study, including letter dated Feb 16, 1970 from J. Becton to Stan Pruss; CDL:006629

- K)

94180 Hughes, J.S. (1970) Letter sent to Athel McMahon dated Feb 10, 1970 ?Toxicity of Princep 80 W and Ametryne|: 71201. (Lou

- isiana, Wild Life and Fisheries Commission; unpublished study, including letter dated F eb 16, 1970 from J. Becton to Stan Pruss; CDL:220070

- A)

106510 Macek, K.; Sleight, B. (1971) Acute Toxicity of Some Ciba

- Geigy Experimental Chemicals to Fathead Minnows (Pimephales promelas). (Unpublished study received on unknown date under 3G1394; pre

- pared by Bionomics, Inc., submitted by Ciba

- Geigy Corp., Ardsley, NY; CDL:093722

- L)

115791 Beliles, R.; Scott, W.; Knott, W. (1964) Ametryne Safety Evaluation in Fish and Wildlife (Final Report) ( Rainbow Trout , Mallard Duck, Oysters). (Unpublished study received Aug 30, 1965 under unknown admin. no.; prepared by Woodard Research Corp., submitted by Ciba

- Geigy Corp., Greensboro, NC; CDL:129363

- A)

115792 McCann, J. (1970) ?Ametryne 80W: Rainbow Trout (Salmo gairdneri)|: Test No. 254. (U.S. Agricultural R esearch Service, Pesticides Regulation Div., Animal Biology Laboratory; unpublished study; CDL:129704

- A)

116257 or 33706 Beliles, R.; Woodard, G. (1964) Ametryne: Acute Toxicity in Sun

- fish. (Unpublished study received Dec 29, 1977 under 100

- 579; prepar ed by Woodard Research Corp., submitted by Ciba

Geigy Corp., Greensboro, NC; CDL:232548

- C)

165368 Woodard Research Corp. (1965?) Ametryne...Acute Toxicity in Rainbow Trout. Unpublished study. 3 p.

40995804 Surprenant, D. (1989) Ametryn: Acute Toxicity of Ametryn Technical to Bluegill (Lepomis macrochirus) Under Static Conditions: Study No. 89

- 1

- 2917. Unpublished study prepared by Springborn Life Sciences, Inc. 43 p.

40995805 Surprenant, D. (1989) Ametryn: Acute Toxicity of Ametryn Technical to Rainbow Trout (Salmo gairdneri) Under Static Conditions: Stu

- dy No. 89

- 1

- 2919. Unpublished study prepared by Springborn Life Sciences, Inc. 42 p.

### 45 42861601 Ward, T.; Kowalski, P. (1993) Acute Toxicity of Ametryn Tec hnical to the Fathead Minnow, Pimephales promelas: Lab Project Number: 219

- CG. Unpublished study prepared by T.R. Wilbury Labs, Inc. 31 p.

42861602 Ward, T.; Kowalski, P. (1993) Acute Toxicity of Ametryn Technical to the Rainbow Trout, Oncorhynchus mykis s: Lab Project Number: 220

- CG. Unpublished study prepared by T.R. Wilbury Labs, Inc. 31 p.

45202909 Grande, M.; Andersen, S.; Berge, D. (1994) Effects of pesticides on fish: experimental and field studies. Norwegian Journal of Agricultural Sciences Suppl. 13: 195

- 209.

92002043 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995804. Acute Toxicity of Ametryn Technical to Bluegill (Lepomis macrochirus) under Static Conditions: Report No. 89

- 1

- 2917. Prepared by SPRINGBORN LIFE SCIENCES, INC. 16 p.

92002044 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995805. Acute Toxicity of Ametryn Technical to Rainbow Trout (Salmo gairdneri) under Static Conditions: Report No. 89

- 1

- 2919. Prepared by Springborn Life Sciences Inc. 15 p.

116258 Hutchinson, C. (1971) Continuous Exposure of Bluegill ... to Ametryne in Water. (Unpublished study received Dec 29, 1977 under 100

- 579; prepared by Bionomics, Inc., submitted by Ciba

Geigy Corp., Greensboro, NC; CDL:232548

- G)

40098001 Mayer, F.; Ellersieck, M. (198 6) 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 Invertebrates
MRID Citation Refere nce

158301 Vilkas, A. (1977) Acute Toxicity of Ametryn FL

- 761356 to the Water Flea: Daphnia magna Straus: Project No. 11506

- 04

- 01. Unpublish

- ed study prepared by Union Carbide Environmental Services. 10 p.

40995806 Surprenant, D. (1989) Ametryn: Acute Toxicity of Ametryn Technical to Daphnids (Daphnia magna) under Static Conditions: Study No. 89

- 1

- 2912. Unpublished study prepared by Springborn Life Sciences, Inc. 44 p.

92002007 Plautz, J. (1990) Ciba

- Geigy Corp. P hase 3 Summary of MRID 40995806. Acute Toxicity of Ametryn Technical to Daphnia Magna Under Static Conditions: Report No. 89

- 1

- 2912. Prepared by SPRINGBORN LIFE SCIENCES INC. 15 p.
72

- 3 Acute Toxicity to Estuarine/Marine Organisms
MRID Citation Ref erence

27094 Lowe, J.I. (1964) Gulf Shellfish: Effects of Pesticides. (Unpub

- lished study including letter dated Jul 28, 1964 from J.I. Lowe to H.E. Fairchild, received Jul 28, 1964 under unknown admin. no.; prepared by U.S. Fish and Wildlife Service, Bureau of Com

- m ercial Fisheries, submitted by Ciba

- Geigy, Greensboro, N.C.; CDL:131211

- A)

80620 Beliles, R.P.; Scott, W.; Knott, W.; et al. (1961) Ametryne: Effect on Shell Growth of Oysters. (Unpublished study received Mar 27, 1967 under 8F0638; prepared by Woodard Re search Corp., submitted by Geigy Chemical Corp., New York, N.Y.; CDL:091109

- N)

41114901 Surprenant, D. (1989) Acute Toxicity of Ametryn Technical To Mysid Shrimp (Mysidopsis bahia) under static Conditions: Study No. 89

- 3

- 2960. Unpublished study prepared by Springborn

### 46 Life Sciences, Inc. 47 p.

41114902 Surprenant, D. (1989) Acute Toxicity of Ametryn Technical To Sheep

- shead Minnow (Cyprinodon variegatus) under Static Conditions: Study No. 89

- 4

- 2967. Unpublished study prepared by Springborn Life Science s, Inc. 43 p.

41114903 Surprenant, D. (1989) Acute Toxicity of Ametryn Technical to Quahog Clam (Mercenaria mercenaria) Embryos

- Larvae under Static Condi

- tions: Study No. 89

- 4

- 2971. Unpublished study prepared by Springborn Life Sciences, Inc. 47 p.

42325201 Surprenant, D. (1989) Supplement to Acute Toxicity of Ametryn Technical to Quahog Clam (Mercenaria mercenaria) Embryos

- Larvae under Static Conditions. Unpublished study prepared by Ciba

- Geigy Corp. 6 p.

92002008 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41114902. Acute Toxicity of Ametryn Technical to Sheepshead Minnow (Cyprinodon Varieqatus) Under Static Conditions: Report No. 89

- 4

- 2967. Prepared by SPRINGBORN LIFE SCIENCES, INC. 18 p.

92002009 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41114903. Acute Toxicity of Ametryn Technical to Quahog Clam (Mercenaria mercenaria) Embryos

- Larvae Under Static Conditions: Report No. 89

- 4

- 2971. Prepared by SPRINGBORN LIFE SCIENCES, INC. 16 p.

92002010 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41114901. Acute Toxicity of Ametryn Technical to Mysid Shrimp (Mysidopsis bahia) under Static Conditions: Report No. 89

- 3

- 2960. Prepared by SPRINGBORN LIFE SCIENCES, INC. 18 p.

33707 Lowe, J.I. (1964) Annual Report: July 1, 1963

- June 30, 1964: Pro

- grams: Gulf Shellfish: Effects of Pesticides. (Unpublished study including letter dated Jul 28, 1964 from J.I. Lowe to H.E. Fairchild, received on unknown date under 100

- 473; prepared by U. S. Fish and Wildlife Service, Bureau of Commercial Fisheries, Biological Laboratory, submitted by Ciba

- Geigy Corp., Greens

boro, N.C.; CDL:000475

- E)

48237 Woodard Research Corporation (1961?) Ametryne: Effect on Shell Growth of Oysters. (Unpublished study received Jul 23, 1965 under unknown admin. no.; submitted by Ciba

- Geigy Corp., Greens

- boro, N.C.; CDL:222959

- C)

40228401 Mayer, F. (1986) Acute Toxicity Handbook of Chemicals to Estuarine Organisms: EPA/600/X/86/231. Prepared by US EPA Environmental Research Laboratory, Gulf Breeze, Fl. 275 p. Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study and 850.1350 Mysid Chronic toxicity
MRID Citatio n Reference

32791 Lowe, J.I. (1964) Effects of Pesticides

-- Laboratory Studies. (Un

- published study received Apr 12, 1965 under 100

- 471; prepared by U.S. Fish and Wildlife Service, Bureau of Commercial Fisheries, submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL:000460

- A )

33310 Loyal, S.W. (1969) An Investigation into the Effects of Simazine 80 WP, Ametryne 25 E, and GS14260 80 WP at 5, 1, .5, and .1 PPM on Bluegill (?~Lepomis_macrochirus~?) in Small Field Ponds. (Unpublished study including letter dated Nov 13, 1970 fr om J.A. Norton to J.E. Dorr, received May 16, 1973 under 1769

- 234; pre

- pared by California State Polytechnic College, submitted by NCH Corp., National Chemsearch Div., Irving, Tex.; CDL:221976

- O)

41189702 McNamara, P. (1989) Ametryn: The Chronic Toxicit y of Ametryn Tech

- nical to Daphnia Magna Under Flow

- through Conditions: Study No. 89

- 6

- 3002. Unpublished study prepared by Springborn Laborato

- ries, Inc. 50 p.

41189703 Surprenant, D. (1989) Ametryn: The Toxicity of Ametryn Technical to Fathead Minnow

### 47 (Pimephales Promelas) Embryo and Larvae: Study No. 89

- 7

- 3022. Unpublished study prepared by Springborn Labora

- tories, Inc. 48 p.

42325202 McNamara, P. (1989) Supplement to the Chronic Toxicity of Ametryn Technical to Daphnia magna under Flow

- through Conditions. Unpublished study prepared by Ciba

- Geigy Corp. 55 p.

42325203 Surprenant, D. (1989) Supplement to the Toxicity of Ametryn Technica l to Fathead Minnow (Pimephales promelas) Embryos and Larvae. Unpublished study prepared by Ciba

- Geigy, Inc. 36
p.

92002011 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41189703. Toxicity of Ametryn Technical to Fathead Minnow (Pimephales Promelas) Embryos and Larvae: Report No. 89

- 7

- 3022. Prepared by SPRINGBORN LAB, INC. 18 p.

92002012 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 41189702. Chronic Toxicity of Ametryn Technical to Duphnia Magna Under Flow

- through Condition s: Report No. 89

- 6

- 3002. Prepared by SPRINGBORN LABS, INC. 19 p.

47399001 Lee, M. (2008) Ametryn: Life

- Cycle Toxicity Test with Mysids (Americamysis bahia): Final Report. Project Number: 1781/6689, T013322/05. Unpublished study prepared by Springborn Smi thers Laboratories. 124 p.
72

- 7 Simulated or Actual Field Testing
MRID Citation Reference

43665 Macek, K.J.; Sleight, B.H., III (1971) Bioassay Report: Acute Toxicity of Some Ciba

- Geigy Experimental Chemicals to Fathead Minnows (Pimephales promelas). (Unpublished study received Apr 27, 1977 under 100

- 541; prepared by Bionomics, Inc., submitted by Cib a

- Geigy Corp., Greensboro, N.C.; CDL:229607

- S)

123

- 1 Seed germination/seedling emergence and veg e tative vigor
MRID Citation Reference

40995807 Canez, V. (1988) Ametryn: Nontarget Phytotoxicity Test: Seed Germi

- nation Tier 2: Study No. LR88

- 55B. Unpublished study prepared by Pan

- Agricultural Labs, Inc. 72 p.

40995808 Canez, V. (1988) Ametryn: Nontarget Phytotoxicity Test: Seedling Emergence Tie r 2: Study No. LR88

- 55C. Unpublished study pre

- pared by Pan

- Agricultural Labs, Inc. 281 p.

40995809 Canez, V. (1989) Ametryn: Nontarget Phytotoxicity Test: Vegetative Vogor Tier 2: Study No. LR 88

- 55A. Unpublished study prepared by Pan

- Agricultural Labs , Inc. 281 p.

92002030 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995807. Nontarget Phytotoxicity: Tier 2 Seed Germination Test with Ametryn Technical: Report No. LR88

- 55B. Prepared by PAN

- AGRICULTURAL LABS, INC. 18 p.

92002031 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995808. Nontarget Phytotoxicity; Tier 2 Seedling Emergence Test with Ametryn Technical: Report No. LR88

- 55C. Prepared by PAN

- AGRICULTURAL LABS. 23 p.

92002032 Plautz, J. (1990) Ciba

- Geigy Corp . Phase 3 Summary of MRID 40995809. Nontarget Phytotoxicity: Tier 2 Vegetative Vigor Test with Ametryn Technical: Report No. LR88

- 55A. Prepared by PAN

- AGRICULTURAL LABS, INC. 22 p.

21912 Coupland, R.T.; Skoglund, N.A. (1962) Response of native grasses to various herbicides, 1962. Pages 124

- 125,~In~Research Report for the National Weed Committee, Western Section:

### 48 Volume 9. Edmon

- ton, Alberta: Natl. Weed Comm.; Pages 84

- 85,~In~19th Annual Research Report for the North Central Weed Control Conference; Dec 3

- 5, 1962, St. Paul, Minn. N.P. (Univ. of Saskatchewan, Dept. of Plant Ecology, Contribution # 340; also~In~unpublished submission received Sep 10, 1968 under 876

- 29; submitted by Velsicol Chemical Corp., Chicago, Ill.; CDL:005055

- A)
123

- 2 Aquatic p lant growth 850.4400 Lemna spp Toxicity test
MRID Citation Reference

40995810 Hughes, J. (1989) Ametryn: The Toxicity of Ametryn Technical to Selenastrum capricornutum: Study No. 0267

- 42

- 1100

- 1. Unpublish

- ed study prepared by Malcolm Pirnie, Inc. 38 p.

92002033 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995810. The Toxicity of Ametryn Technical to Selenastrum Capricornutum: Report No. 0267

- 42

- 1100

- 1. Prepared by MALCOLM PIRNIE, INC. 17 p.

47399002 Softcheck, K. (2007) Ametryn: 7

- Day Toxicity T est with Duckweed (Lemna gibba): Amended Final Report. Project Number: 1781/6688, T013324/05. Unpublished study prepared by Springborn Smithers Laboratories. 62 p.

47954502 Ma, J.; Liang, W.; Xu, L.; et al. (2000) Acute Toxicity of 33 Herbicides to the Gr een Alga Chlorella pyrenoidosa. Bulletin of Environmental Contamination and Toxicology 66:536

- 541.

47954503 Ma, J. (2001) Differential Sensitivity to 30 Herbicides Among Populations of Two Green Algae Scenedesmus obliquus and Chlorella pyrenoidosa. Bullet in of Environmental Contamination and Toxicology 68:275

- 281.

40228401 Mayer, F. (1986) Acute Toxicity Handbook of Chemicals to Estuarine Organisms: EPA/600/X/86/231. Prepared by US EPA Environmental Research Laboratory, Gulf Breeze, Fl. 275 p.
141

- 1 Honey bee acute contact

MRID Citation Reference

40995811 Hoxter, K.; Jaber, M. (1988) Ametryn: An Acute Contact Toxicity Study with the Honey Bee: Project No. 108

- 288. Unpublished stu

- dy prepared by Wildlife International Ltd. 15 p.

92002034 Plautz, J. (1990) Ciba

- Geigy Corp. Phase 3 Summary of MRID 40995811. Acute Contact Toxicity of Ametryn Technical to the Honey Bee: Report No. 108

- 288. Prepared by WILDLIFE INTERNATIONAL LTD. 13 p.

Non Target Insect Toxicity Testing
7897 Leigh, T.F. (196 6) LDI50^ Values and~b~Values for 34 Insecticides When Applied Topically to Adult Male and Female~Lygus hesperus~ Knight: Shafter, California: 1960

- 1966: Table 1. (Unpublished study including letter dated Sep 19, 1967 from T.F. Leigh to Donald L. Burgoyne, received Apr 16, 1971 under 1G1144; prepared by Univ. of California

-- Davis, Agricultural Experiment Station, Dept. of Entomology, submitted by E.I. du Pont de Nemours & Co., Inc., Wilmington, Del.; CDL:090931

- B)

Non Guideline
28430 Ballantine, L.G.; Holt, B.E.; Akesson, N.B.; et al. (1980) Poten

- tial Hazard to Nontarget Plants Resulting from Aerial Appli

- cations of Aatrex^(R)I, Bicep^(R)I, Dual^(R)I, Evik^(R)I, Igran^(R)I, Milocep^(R)I, Sancap^(R)I, Aatrex + Karmex^(R)I, Aatrex + E vik, Dual + Aatrex, Dual + Lorox^(R)I, Dual + Lex

- one^(R)I/Sencor^(R)I, Evik + Karmex, and Igran + Aatrex:

### 49 Report No. ABR

- 80014. (Unpublished study including published data, re

- ceived Apr 29, 1980 under 100

- 439; prepared in cooperation with Univ. of Cali fornia

-- Davis, Agricultural Engineering Dept. and others, submitted by Ciba

- Geigy Corp., Greensboro, N.C.; CDL: 242535

- A)

50459 E.I. du Pont de Nemours & Company (1971) Environmental and Wildlife Information Relating to the Use of Lannate Methomyl Insect icide in Pineapple in Hawaii. (Reports by various sources; unpub

- lished study including published data, received Jan 6, 1981 un

- der 352

- EX

- 106; CDL:099858

- A)

116259 Macek, K.; Sleight, B. (1971) Preliminary Investigations of the Accumulation of Ametryn e Residues by Bluegill Continuously Exposed to Ametryne in Water. (Unpublished study received Dec 29, 1977 under 100

- 579; prepared by Bionomics, Inc., sub

- mitted by Ciba

- Geigy Corp., Greensboro, NC; CDL:232548

- H)

### 50 A ppendix B

. Biological and Economic Analysis Division (BEAD) Report

BEAD Chemical Profile: Ametryn

### 51 E FED’s Label Data Report for Ametryn as of 1/31/13

Use Site Application Method

Type Application Method Equipment Formulation Desc Application Method Timing Original (Product / A. I.) Max App Rate A. I. Max App Rate Max # Apps @ Max Rate /

CC A. I. Max App Rate/ Year Product Seasonal

Max Dose/CC Minimum Retreat

ment Interval

Corn, Field Basal spray
treatment Sprayer Dry Flowable Foliar 2 lb/ 1 a 1.578 lb / a NS NS NS NS

Corn, Field Spray Sprayer Dry Flowable Post

emergence 2 lb/ 1 a 1.578 lb / a NS NS NS NS

Corn, Pop Basal spray
treatment Sprayer Dry Flowable Foliar 2 lb/ 1 a 1.578 lb / a NS NS NS NS

Corn, Pop Spray Sprayer Dry Flowable Post

emergence 2 lb/ 1 a 1.578 lb / a NS NS NS NS

Pineapple Broadcast. Sprayer Dry Flowable Ratoon 2 lb/ 1 a 1.578 lb / a NS NS 4 lb / a NS

Pineapple Spray Sprayer Dry Flowable Post

- plant 2 lb/ 1 a 1.578 lb / a NS NS 4 lb / a NS

Pineapple Spray Sprayer Dry Flowable Preharvest 2 lb/ 1 a 1.578 lb / a NS NS 4 lb / a NS

Sugarcane Band
treatment Ground Dry Flowable Ratoon 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Basal spray
treatment Sprayer Dry Flowable Ratoon 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Aircraft Dry Flowable Foliar 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Ground Dry Flowable Preemergence 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Ground Dry Flowable Ratoon 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Sprayer Dry Flowable Post

emergence 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Sprayer Dry Flowable Preemergence 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

Sugarcane Broadcast Sprayer Dry Flowable Ratoon 1.5 lb/ 1 a 1.1835 lb / a NS NS 3 lb / a NS

### 52 Appendix C

. Output from OPP Aggregate Incident Database for Ametryn 

# Aggregate Incident Report for EFED Ametryn
PC Code: 080801



## Total Count of Minor Incidents from Aggregated Reports

Minor Fish and Wildlife Incidents (W

- B): 0 Minor Plant Incidents (P

- B): 0 Minor "Other Nontarget" Incidents (ONT): 0

### 53 Appendix D

. SIP Results for Evaluate Potential Risk to Birds and Mammals from Drinking Water Exposure.

Table 1. Inputs Parameter Value Chemical name Ametryn Solubility (in water at 25 o C; mg/L) 185

Mammalian LD 50 (mg/kg-bw) 1009 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species Mammalian NOAEL (mg/kg-bw) 14 Mammalian test species laboratory rat Body weight (g) of "other" mammalian species

Avian LD 50 (mg/kg-bw) 2250 Avian test species northern bobwhite quail Body weight (g) of "other" avian species Mineau scaling factor 1.15 Mallard NOAEC (mg/kg-diet) 562 Bobwhite quail NOAEC (mg/kg-diet) 1780 NOAEC (mg/kg-diet) for other bird species 0 Body weight (g) of other avian species NOAEC (mg/kg-diet) for 2nd other bird species 0 Body weight (g) of 2nd other avian species

Table 2. Mammalian Results Parameter Acute Chronic Upper bound exposure (mg/kg-bw) 31.8200 31.8200 Adjusted toxicity value (mg/kg-bw) 776.0830 10.7682 Ratio of exposure to toxicity 0.0410 2.9550

Conclusion* Drinking water exposure alone is NOT a potential

concern for mammals Exposure through drinking water alone is a potential

concern for mammals

Table 3. Avian Results Parameter Acute Chronic Upper bound exposure (mg/kg-bw) 149.8500 149.8500 Adjusted toxicity value (mg/kg-bw) 1620.9664 27.8823 Ratio of exposure to acute toxicity 0.0924 5.3744

Conclusion* Drinking water exposure alone is NOT a potential concern for birds Exposure through drinking water alone is a potential concern for birds

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

### 54 Appendix E

. STIR Results to Evaluate the Potential for Inhalation Risk to Birds and Mammals



## Welcome to the EFED Screening Tool for Inhalation Risk This tool is designed to provide the risk assessor with a rapid method for determining the potential significance of the inhalation exposure route to birds and mammals in a risk assessment.


### Input

Application and Chemical Information Enter Chemical Name Ametryn Enter Chemical Use Herbicide Is the Application a Spray? (enter y or n) y If Spray What Type (enter ground or air) ground Enter Chemical Molecular Weight (g/mole) 227.3 Enter Chemical Vapor Pressure (mmHg) 2.74E-06 Enter Application Rate (lb a.i./acre) 2.4

Toxicity Properties
**Bird** Enter Lowest Bird Oral LD 50 (mg/kg bw) 2250 Enter Mineau Scaling Factor 1.15 Enter Tested Bird Weight (kg) 0.178 **Mammal** Enter Lowest Rat Oral LD 50 (mg/kg bw) 1009 Enter Lowest Rat Inhalation LC 50 (mg/L) 5.03 Duration of Rat Inhalation Study (hrs) 4 Enter Rat Weight (kg) 0.35 

### Output Results Avian (0.020 kg ) Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 3.35E-02 Maximum 1-hour Vapor Inhalation Dose (mg/kg) 4.21E-03 Adjusted Inhalation LD 50 6.25E+01 Ratio of Vapor Dose to Adjusted Inhalation LD 50 6.74E-05 Exposure not Likely Significant Maximum Post-treatment Spray Inhalation Dose (mg/kg) 2.54E-01 Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 4.06E-03 Exposure not Likely Significant

Results Mammalian (0.015 kg ) Maximum Vapor Concentration in Air at Saturation (mg/m 3 ) 3.35E-02 Maximum 1-hour Vapor Inhalation Dose (mg/kg) 5.30E-03 Adjusted Inhalation LD 50 2.99E+02 Ratio of Vapor Dose to Adjusted Inhalation LD 50 1.77E-05 Exposure not Likely Significant Maximum Post-treatment Spray Inhalation Dose (mg/kg) 3.19E-01 Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD 50 1.06E-03 Exposure not Likely Significant **NOTE**: When entering values, press order to update linked cells.

### 55 Appendix F. Environmental Fate and Transport Characterization

Available data indicate that ametryn is stable to hydrolysis at environmental pHs (MRID 40995812). Aqueous photolysis (MRID 41169601) and photodegradation on soil studies (MRIDs 41169602, 41169603 ) were reclassified as not acceptable due to multiple
exper imental method deficiencies. Although aqueous photolysis data are needed to adequately characterize the fate of ametryn in aquatic environments, new data for photodegradation on soil are not considered likely to be useful, as that degradation pathway is e xpected to be of limited significance in the environment, where aerobic soil degradation and soil mobility will have a greater effect on the fate of the compound.

Available soil metabolism data demonstrate that ametryn biodegrades in aerobic soil, with half

- lives of approximately 10 days (MRID 46533801) and 40 days (MRID 41752401) , indicating that it will be nonpersistent to slightly persistent (based on Goring et al. 1975 ) in such soil. However, data are only available for two soils, and the 10

- day hal f

- life may underestimate the degradation of ametryn given that there were high percentages of unextracted residues in the study (20% of the applied by 14 days, 41% by 56 days, and 64% by 171 days). In that study (MRID 46533801), a transformation pathway w as proposed by the study author in which ametryn rapidly degraded to the sulfoxide, NOA 423271, then further oxidized to the sulfonic acid, NOA 428383. NOA 423271 was hydroxylated to G 34048 and subsequently oxidized to NOA 438707. In a second pathway, a metryn degraded to GS

- 11355 and GS

- 11354. GS

- 11354 was hydroxylated to GS

- 17794. The proposed endpoint of the pathway is the mineralization of the metabolites to carbon dioxide and the formation of bound residues. Data for three additional soils, repres entative of intended use areas, are needed to more completely characterize the aerobic soil degradation of ametryn.

Available anaerobic soil and anaerobic aquatic metabolism data indicate that ametryn is stable to degradation and thus persistent (based on Goring et al. 1975 ) under flooded/anaerobic conditions. In both of the anaerobic soil metabolism studies, the

concen tration of parent increased during the flooding period (relative to pre

- flood levels). It is possible that the potential transformation products NOA 432271 (sulfoxide of ametryn) and NOA

- 428383, oxidized forms of ametryn which can undergo reduction when t he redox potential is below

- 148 mV, were reduced back to the parent compound; however, they were not monitored in one of the studies (MRID 41752401 ). In one anaerobic soil metabolism study, unextracted residues were 20% at flooding, and 31

- 35% at 28

- 150 days (MRID 46533801). Harsh extraction of the 150

- day sample released an additional 7.0% of the applied; G 34048 was the predominant compound in these extracts at 3.5% of the applied. Fractionation of the nonextracted residues in the 150

- day harsh

extrac ted soil (26.9% of the applied) determined that 7.1%, 8.5%, and 11.3% of the applied was associated with fulvic acids, humic acids, and humin, respectively. In the anaerobic aquatic metabolism studies, unextracted residues were <6.8% throughout one study (MRID 46533801) and were 14

- 17% at 360 days (MRID 42861603) in the other study.

### 56 There are no available aerobic aquatic metabolism data. While a data waiver was approved in the past for this guideline requirement, data are now considered necessary in

or der to more fully understand the fate of ametryn and its transformation products in the environment. In the past, a default value of two times the aerobic soil metabolism half

live was used for modeling. However, given the persistence of the compound in flooded/anaerobic conditions, as well as the potential for the transformation products NOA 432271 and NOA 428383, which are oxidized forms of ametryn, to undergo reduction back to parent ametryn when the redox potential is below

- 148 mV, the use of a defau lt value derived from aerobic soil metabolism half

- lives may greatly overestimate the potential for degradation in an aerobic aquatic environment.

Ametryn is expected to be mobile to moderately mobile in soil based on the FAO mobility classification sch eme (FAO, 2000) and organic

- carbon normalized partition coefficients (K oc 

### ) that ranged from 96 to 927 in four soils (MRID 40995813). In aged (MRID 41169605) and unaged (MRID 41169604) column leaching experiments, ametryn leached through sandy loam (aged a nd unaged), loam (unaged) and sand (unaged) soil columns, and was detected in the leachate from the columns. In a clay soil column, ametryn was less mobile, but was still detected at a depth of 8 inches and at low levels in the leachate. Although there a re no batch equilibrium data for the transformation products, in the aged soil column studies, all of the compounds monitored (GS

- 34048; GS

- 11354; GS

- 11355; GS

- 26831; GS

- 32083 ; GS

- 28304; and GS

- 17794; see Section 3.1 for identifications) were mobile ( i.e
., showed leaching) in sandy loam soil, and all except GS

- 17794 were detected in the leachate. All of the compounds studied were more mobile than the parent. Thus, ametryn and many of its transformation products may potentially leach to groundwater. There ar e no mobility data on the major transformation products NOA 423271 and NOA 428383, which are oxidized forms of ametryn and can be reduced back to parent under certain environmental conditions

. 

### Field studies were conducted on bareground and corn plots (san d soils) in IL, and a sugarcane plot in LA (silty loam soil ). All of the studies were classified as supplemental due to both experimental and analytical method deficiencies. In each of the field studies, ametryn dissipated more rapidly in an initial phase (30 or 60 days), followed by a period of slower degradation. Dissipation half

- lives calculated from the complete data sets were 35 days (IL corn), 48 days (IL bareground), and 62 days (LA sugarcane). In both of the IL sand plots, ametryn was detected to a maximum depth of 12 inches and G

- 34048 was detected at all depths to 48 inches. In the LA silty loam plots, ametryn was detected to a maximum depth of 6 inches and G

- 34048 was detected to a maximum depth of 6 inches, with the exception of two detection s below 6 inches. The transformation products GS

11794 and GS

- 11354 were also detected in all plots to a maximum depth of 6 inches. It is unclear whether the aerobic soil metabolism transformation products, NOA 423271 and NOA 428383, which are of toxic c oncern, were monitored in any of the studies.

Ametryn that reaches aquatic habitat (through spray drift and/or runoff) is not likely to accumulate in tissues of aquatic organisms, as indicated by the results of a bioconcentration study conducted on bluegi ll sunfish ( Lepomis macrochirus ).

### 57 Bioconcentration factors (BCF) were: 61X in edible tissues, 110X in non

- edible tissues, and 83X in whole fish. During depuration, with 60

- 80% of accumulated 14 

### C residues were eliminated from the fish tissues after 28 days. The transformation products identified in the edible and nonedible tissues GS

- 11354, GS

- 11355, di

- amino ametryn (GS

- 26831), GS

- 11354 sulfoxide, a cysteine conjugate of 2

- ethylamino

- 4

- isopropyl amino s

- triazine, 2

- hydroxy

- 4

- isopropylamino

- 6

- N

- acetyl cysteine s

- triazine, a cystine conjugate of ametryn, and 4

- isopropylamino

- 2,6

- diamino triazine.

In a registrant

- submitted groundwater monitoring study conducted on multiple triazines, ametryn was det ected in only 2 of 413 well samples in 2001, at 0.12 and 0.21 ppb (LOQ = 0.10 ppb; MRID 45629801). In 2002, ametryn was not detected in any of the 80 well samples (LOQ = 0.10 ppb; MRID 45870401).

In a small

- scale retrospective groundwater monitoring stu dy at two turf sites in Florida, ametryn was detected in six of 13 wells at concentrations of 0.14

– 1.5 ppb in August 1993. The ametryn transformation product GS

- 11354 was detected in one well, at 0.13 ppb (MRID 43141400 )

. Monitoring in Hawaii of ground water in pineapple use areas in the 1990's resulted in a maximum ametryn concentration similar in magnitude to that predicted (9.8 ppb) for TTR with the groundwater screening model SCIGROW ( USEPA 2005). Samples were collected by the Ciba

- Geigy Corporation from 1992 to 1994, and analyzed for residues of atrazine and ametryn. Ametryn degradates GS

- 11354, GS

- 26831 and rarely GS

- 11355 were also included as analytes. Ametryn was rarely detected in groundwater samples, although the maximum concentration detected was 7.6 ppb. Degradates of ametryn were not detected in any sample.

Quarterly surface

- water monitoring from the South Florida Water Management District’s (SFWMD, 2012 inter al .) quarterly ambient monitoring program 

### on the borders of the Everglades Agric ultural Area (EAA) has resulted in surface water concentrations well below those estimated in the past (USEPA 2005) for maximum application rates by the PRZM/EXAMS models

. 

### However, the frequency of the sampling is not sufficient for the estimation of pot ential acute exposure, nor extensive enough to allow a conservative estimate of potential chronic exposure.

Ametryn was detected in pesticide monitoring conducted from 2004 to 2008 in the developed floodplain of the lower Burdekin River and downstream ma rine environments in Australia during high and low flow conditions (Davis et al ., 2008). Ametryn and other pesticides associated with sugarcane use were among the ones detected at the highest concentrations during low flow conditions. Ametryn was detecte d at 80 of 143 sampling locations, at a range of ≤ 0.1 0.31 ug/L (e vent flow conditions) and ≤0.1

– 2.10 ug/L (ambient flow conditions). The analytical detection limit was 0.1 ug/L.