UNITED STATES ENVIRONMENTAL J>ROTECTION AGENCY 

W ASHJNGTON D.C., 20460 

OFFICE OF CHEMICAL SAFETY 

AND POLLUTION PREVENTION 

PC Code: 101 103 

DP Barcode: 408388 

April29, 2013 

MEMORANDUM 

Subject: 

To: 

Through: 

From: 

Registration Review: Preliminary Problem Formulation for Pymetrozine 

Steven Snyderman, Chemical Review Manager 

Patricia Parrott, Chief 

Risk Management and Implementation Branch III 

Pesticide Re-evaluation Division (7508P) 

Dana Spatz, Branch Chi-~~~~;:,.;;~~­

Melissa Panger, Ph.D., Semor 

Environmental Risk Branch Ill 

Environmental Fate and Effects Division (7507P) 

ochelle Bohaty, Ph.D., Chemist 

ames 

atherine 

Hetrick, 

R. Stebbins, 

Ph.D., Senior 

Biologist

Advisor 

~ 

~w .,. 

Rosanna Louie-Juzwiak, RAPL 

Environmental Risk Branch Ill 

Environmental Fate and Effects Division (7507P) 

The Environmental Fate and Effects Division (EFED) has completed the problem formulation in 

support of the Registration Review of the insecticide, pymetrozine (attached). This document is 

intended to provide an overview of what is currently known regarding the environmental fate and 

ecological effects associated with pymetrozine and its transformation products. Uncertainties 

regarding attributes of the parent compound and its transformation products are also outlined. It 

describes the preliminary ecological risk hypothesis and the processes that will be used during 

the completion of ecological risk assessment in support of registration review. 

1 
2 

Introduction 

Pymetrozine is a pyridine azomethine insecticide that is currently registered for use on 

ornamental plants, non-bearing fruit and nut trees in nurseries, Christmas trees, and a variety of 

agricultural crops. This group of insecticides exhibits a unique mode of action characterized as 

neural inhibition of feeding behavior in its target pests (insects in the order Homoptera-includes 

aphids, whiteflies, and leafhoppers). Details of pymetrozine’s nervous system action are not fully 

understood, but it is thought to work by affecting serotonin or the chordotonal organs in the 

insect nervous system.1,2 Pymetrozine works primarily by ingestion but also has some contact 

activity. Pymetrozine has residual activity in the plant and will control pests that move onto the 

plant after spraying. The chemical structure of pymetrozine, as well as the chemical name and 

other identifiers are provided in Table 1. 

Table 1. Pymetrozine Chemical Identifiers

Parameter Identifier 

Chemical Structure HN

N

N N N

CH3

O

Chemical Name (4,5-dihydro-6-methyl-4-[(3-pyridinylmethylene) amino]-1,2,4-triazine-3(2H)-one) 

1,2,4-triazin-3(2H)-one, 4,5-dihydro-6-methyl-4-[(3-pyridinylmethylene) amino] 

SMILES O=C1NN=C(C)CN1N=Cc2cccnc2 

CAS Number 123312-89-0 

Company Code CGA 215944 

Use Characterization 

There are two end use products for pymetrozine (Fulfill® and Endeavor®) and both are 

formulated as water dispersible granules. Foliar spray applications may be made using ground 

and aerial equipment (except for non-agricultural uses, and use on hops and tobacco). 

Additionally, chemigation applications are allowed for use on potatoes except in the state of 

California (chemigation applications are prohibited for potatoes in CA). 

The Fulfill® label (EPA Reg. No. 100-9112), which has the crop uses, lists the maximum 

application rates on a seasonal (per crop cycle) rather than annual basis so during the assessment, 

the number of crop cycles per year will need to be considered. Additionally, the SLN label for 

use on tomatoes grown for transplant (FL030004) does not provide an application rate (use 

 

1 L. Kaufmann et. al. 2004. The serotonergic system is involved in feeding inhibition by pymetrozine. Comparative 

studies on a locust (Locusta migratoria) and an aphid (Myzus persicae.) Comp. Biochem. Physiol. C-Toxicol. 

Pharmacol. (138) pp 469–483 

2 J. Ausborn et al. 2005. The insecticide pymetrozine selectively affects chordotonal mechanoreceptors J Exp Biol. 

(208) pp. 4451-4466.
3 

instructions state to apply 1.5 oz of product per 100,000 plants) in terms of pounds active 

ingredient per acre (lb a.i./A). 

Table 2 provides a summary of the use patterns and maximum use rates for the current uses of 

pymetrozine. In addition, this table includes the number of crop cycles that may be assumed to 

occur for each crop that does not specially state a yearly application rate. 

Agricultural Use Sites 

Pymetrozine may be applied to various agricultural crops including: alfalfa (under 5 Section 24c 

registrations), asparagus, cole crops, cotton, cucurbit vegetables, fruiting vegetables, hops, leafy 

vegetables, pecans, potatoes, root and tuber vegetables, and tobacco. 

Pymetrozine is registered for two active Section 3 and nine SLN/Section 24c registrations. The 

SLN registrations are for alfalfa (ID, MT, OR, UT, WA); vegetables grown for seed (arugula, 

beet, broccoli raab, Brussels sprouts, cabbage, carrot, cauliflower, chinese cabbage/kale/mustard, 

collard greens, endive, kale, kohlrabi, lettuce, mustard, parsley, parsnip, radish (other than 

daikon), rape, rutabaga, spinach, spinach mustard, Swiss chard, turnip (WA); root vegetables 

grown for seed (OR); tomatoes grown for transplant (FL); and for enhanced management of 

whiteflies in tomatoes (to allow a greater number of applications-FL). 

According to the available usage data, the crops with the highest use in terms of pounds of active 

ingredient (a.i.) applied (2003-2010 average) are potatoes (an average of 4,000 pounds a.i. 

applied annually) followed by cantaloupes, lettuce, pecans, and tomatoes (~ 1,000 pounds a.i. 

applied annually)3

. 

Non-Agricultural Use Sites 

Pymetrozine may be applied to ornamentals grown outdoors (landscape ornamentals/ground 

covers and field or container grown) and also to ornamentals in greenhouses, lath/shadehouses, 

and interiorscapes. Other use sites include non-bearing fruit and nut trees in nurseries and 

Christmas trees. 

Limited usage data are available for non-agricultural uses. For 2002, 2004, and 2006, (the most 

recent years for which non-agricultural survey data are available), less than 500 lb. of 

pymetrozine was reported for nursery/greenhouse uses4

. 

 

3 U.S. EPA. 2012. Screening Level Use Analysis-Pymetrozine. June 21, 2012. 

4 U.S.EPA. 2013. BEAD Chemical Profile for Registration Review: Pymetrozine (PC Code 101103). 
Table 2. Currently Registered Pymetrozine Uses 

Use Site Application Method 

Maximum 

Single 

Application 

Rate 

(lb a.i./A) 

Maximum 

Number of 

Applications 

per Crop 

Cycle 

Maximum 

Application 

Rate per 

Crop Cycle 

(lb a.i./A) 

Number 

of Crop 

Cycles 

Per Yeara 

Maximum 

Number of 

Applications 

per Year 

Maximum 

Application 

Rate per 

Year 

(lb a.i./A) 

MRI 

(days) 

REI 

(hours) 

PHI 

ALFALFA (SLNS for ID, MT, OR, UT, WA) 

Aerial/ 

Ground 0.0859 2b 0.1719 1 2c 0.1719c 7 12 N

ASPARAGUS Aerial/ Ground 0.0859 6b 0.5156 1 6c 0.5156c 30 12 NCHRISTMAS TREES 

Ground 

spray/ 

Containerized 

plant 

0.3125 NS NS 1 

Outdoor: 

5d

Indoor: 

10d 

Outdoor: 1.5 

Indoor: 

3.125 

7 12 N

COLE CROPS Aerial/ Ground 0.0859 2b 0.1719 3 6b 0.5157 7 12 NCOTTON Aerial/ Ground 0.0859 2b 0.1719 1 2c 0.1719 7 12 NCUCURBIT VEGETABLES 

Aerial/ 

Ground 0.0859 2b 0.1719 1 2c 0.1719 7 12 N

FRUITING VEGETABLES 

Aerial/ 

Ground 0.0859 2b 0.1719 1 2c 0.1719 7 12 N
FRUITS (Nonbearing fruit and nut trees in nurseries) 

Ground 

spray/ 

Containerized 

plant 

0.3125 NS NS 1 

Outdoor: 

5d

Indoor: 

10d

Outdoor: 1.5 

Indoor: 

3.125 

7 12 N

HOPS Ground 0.1875 3 0.5625 NS NS 14 12 NLEAFY VEGETABLES 

Aerial/ 

Ground 0.0859 2b 0.1719 2 4c 0.3438 7 12 N

ORNAMENTALS 

Ground 

spray/ 

Containerized 

plant 

0.3125 NS NS 1 

Outdoor: 

5d

Indoor: 

10d

Outdoor: 1.5 

Indoor: 

3.125 

7 12 N

PECAN Aerial/ Ground 0.125 2b 0.25 1 2c 0.25 7 12 NPOTATO, WHITE/IRISH 

Aerial/ 

Ground/ 

Chemigation 

0.1719 2b 0.3438 1 2c 0.3438 7 12 N

ROOT AND TUBER VEGETABLES (Includes Oregon SLN) 

Aerial/ 

Ground 0.1719 2b 0.3438 1 2c 0.3438 7 12 N

TOBACCO Ground 0.0859 2b 0.1719 1 2c 0.1719 7 12 NTOMATO -SLN (FL) for enhanced management-4 apps) 

Aerial/ 

Ground 0.043 4 0.1719 1 NS NS 14 12 N
TOMATO -SLN (FL) for tomatoes grown for transplant 

Aerial/ 

Ground 

1.5 oz 

product per 

100,000 

plants 

2 0.013f 1 2c 0.013c 7 12 N

VEGETABLES grown for seedSLN label (WA) 

Aerial/ 

Ground 0.0859 2b 0.1719 3 6c 0.5157 7 12 N

a. The number of crop cycles per year was derived from the “Maximum Number of Crop Cycles per Year in California for Methomyl Use Sites” memo.5

b. Not specified on the label; however, assumed the maximum application rate per crop cycle divided by the maximum single application rate. c. Not specified on the label; however, assumed the maximum number of applications per crop cycle multiplied by the number of crop cycles possible per d. Not specified on the label; however, assumed the maximum single application rate divided by the maximum yearly application rate. e. 0.75 oz a.i.(50% by weight)/100,000 plants*1.36 g/0.034 oz*1lb/453.6=6.6 x 10-7 lb a.i./plant; 6.6 x 10-7 lb a.i./plant *10,890 plants/acre6 = 6.6 x10-3 lb 

f. Calculated based on 2 applications per crop cycle Not specified (NS) on the label 

5 U.S. Environmental Protection Agency, M. Kaul, Maximum Number of Crop Cycles Per Year in California for Methomyl Use Sites, February 

6 U.S. Environmental Protection Agency, Becker, J., Ratnayake, S. Acres Planted per Day and Seeding Rates of Crops Grown in the United Sta
7 

Conclusions from Previous Risk Assessments 

Ecological Risk Assessments 

EPA has conducted multiple ecological risk assessments for pymetrozine and these assessments 

will serve as a basis for this problem formulation document, as well as for the risk assessment to 

be conducted as part of the registration review. Pymetrozine was first assessed as a new active 

ingredient in 1999. Two new use assessments were conducted in 2000 and 2001, one for use on 

cotton, pecans, leafy vegetables, and brassica (08/00), and another for hops and cotton (05/01). 

In 2004, a new use assessment was conducted for use on asparagus (05/04) and this assessment 

included both the parent, pymetrozine, and the environmental degradate CGA-359009. The most 

recent assessment was conducted in 2006 (07/06) to assess a rate increase for potatoes and other 

tuberous root and corm vegetables. The 2004 asparagus assessment was the only one to include 

the parent and degradate (CGA359009) in the estimated exposures. 

All of the previous assessments up until 2006 stated that there were no risks of concern to 

aquatic or terrestrial organisms from the proposed pymetrozine uses. However, the latest 

assessment conducted in 2006 (to assess a rate increase for potatoes/tuberous and corm 

vegetables) reported a risk to mammals on a chronic exposure basis (RQs ranged from 

0.02-2.41) and also noted that due to a difference in the foliar dissipation half-life that 

was used in some of the previous assessments (35 days in 2006 vs. 5.5 days in earlier 

assessments), there would have also been LOC exceedances in the previous assessments, 

had the 35-day half-life value been used. Table 3 provides a summary of the major 

ecological conclusions presented in the previous risk assessments. 

Drinking Water Exposure Assessments 

A drinking water assessment (DWA) for pymetrozine was conducted at the time of the new 

chemical assessment7

, and updated with each subsequent new use. Exposure estimates from 

these assessments are highlighted in Table 4 and Table 5. A DWA will be conducted to support 

future pymetrozine human health dietary risk assessments. The DWA will incorporate model 

estimates of pymetrozine, as well as any transformation products identified as residues of 

concern in surface water and/or groundwater. Concentrations of pymetrozine residues in drinking 

water will be estimated using EFED aquatic models (e.g., PRZM-EXAMS, SCI-GROW and 

PRZM-GW). The major degradate, CGA359009 is currently considered a residue of concern in 

drinking water8

; however, if any additional environmental transformation products of 

pymetrozine are identified as a potential toxicological concern with similar toxicity as the parent, 

all residues will be considered using a total toxic residue (TTR) approach for the drinking water 

assessment. 

 

7 U.S. Environmental Protection Agency, Nguyen, T. L., Carey, S. EFED New Chemical Environmental Risk 

Assessment for Pymetrozine, DP250387, April 21, 1999. 

8 U.S. Environmental Protection Agency, Drew, W. T., Hurley, P. Pymetrozine on Asparagus. Health Effects 

Division (HED) Metabolism Assessment Review Committee (MARC) Decision Document. DP 292533, October 23, 

2004 
Table 3. Summary of Risk Concerns Identified for Pymetrozine in Previous Assessments 

Exposure 

Basis Birds Mammals 

Terrestrial 

Plants 

Terrestrial 

Inverts. 

(honey bee 

hazard) 

Fish Aquatic Inverts Aquatic Plants Groundwater Contamination Persistenc

Acute -- -- * -- -- -- -- 

-- -- 

Chronic --  * -- -- -- -- * Uncertain due to data gaps 

Table 4. Summary of Prior Drinking Water Assessments for Pymetrozine in Surface Water 

Assessment/ 

Date 

Crop 

Scenario Model Used 

Pymetrozine Pymetrozine and CGA 359

1-in-10 Year 

Peak 

Concentration

μg/L (ppb)

1-in-10 Year 

Annual 

Average 

Concentration 

μg/L (ppb)

30 Year 

Average 

Yearly 

Concentration 

μg/L (ppb)

1-in-10 Year 

Peak 

Concentration

μg/L (ppb)

1-in-10 Y

Annua

Averag

Concentra

μg/L (pp

Emergency 

Exemption 

DP244341 

and 

DP244342 

3/98 

WI Potatoa GENEEC 2.05 1.12b 

Emergency 

Exemption 

DP257655 

7/99 

CA 

Lettuce PRZM/EXAMS 2.13 1.1c 0.422

Emergency 

Exemption 

DP266902 

7/00 

GA 

Pecans GENEEC 4.0 2.3b

Revised 

Assessment 

DP275123 

6/01 

Hops 

FIRST 

13.6 2.7d

Cotton 1.2 0.24d
Refined 

Assessment 

D275123 

11/01 

Cotton 

PRZMEXAMS 

0.73 0.2d

Cucurbit 3.1 0.7d

Tomato 3.7 0.8d

Cabbage 4.4 0.9d

Pecan 5.2 1.6d

Hops 2.7 1.1d

New Use 

Assessment 

DP283937 

10/04 

Asparaguse PRZM- EXAMS 9.0 4.2 2.5 16.3 10.1 

New Use 

Assessment 

DP321675 

7/06 

Potatoes PRZM- EXAMS 7.1 1.8 1.4 

a. 0.086 lb a.i./A; 2 applications; 7 day application interval 

b. 56-day average concentration 

c. 60-day average concentration 

d. Annual average 

e. The maximum single application rate (Maximum single application rate 0.172 lb a.i./A; Maximum application rate per sea

assessed is higher than the maximum single application rate currently registered for asparagus (Maximum single applicatioMaximum application rate per season 0.516 lb a.i./A). 
10 

Table 5. Summary of Prior Drinking Water Assessments for Pymetrozine in Groundwater 

Assessment Crop Model 

Used 

Pymetrozine Pymetrozine and CGA 359009 

(TTR Approach)

Peak 

Concentration 

μg/L (ppb) 

Yearly Mean 

Concentration 

μg/L (ppb) 

Peak 

Concentration 

μg/L (ppb) 

Yearly Mean 

Concentration 

μg/L (ppb) 

Emergency 

Exemption 

DP244341 and 

D244342 

3/98 

WI Potato SCIGROW 0.019 0.019 

Emergency 

Exemption 

DP257655 

7/99 

CA 

Lettuce 

SCIGROW 0.015 0.015 

Emergency 

Exemption 

DP266902 

7/00 

GA 

Pecans 

SCIGROW 0.015 0.015 

New Use 

Assessment 

DP283937 

10/04 

Asparaguse SCIGROW 0.016 0.016 0.038 0.038 

Clean Water Act Programs 

Pymetrozine is not identified as a cause of impairment for any water bodies listed as impaired 

under section 303(d) of the Clean Water Act. No Total Maximum Daily Load (TMDL) criteria 

have been developed for pymetrozine. Aquatic Life Ambient Water Quality Criteria documents 

or Aquatic life benchmarks have not been published for pymetrozine. 

Environmental Fate and Transport 

Parent Pymetrozine 

Physical and Chemical Properties 

The physicochemical properties of pymetrozine are shown in Table 6. Based on these properties 

alone, pymetrozine is not expected to be volatile or to bioaccumulate. It is highly soluble in 

water. 

 
11 

Table 6. Selected Physical/Chemical Parameters of Pymetrozine 

Parameter Value Source/Classification

Molecular Mass (molecular formula) 217.23 g/mol 

(C10H11N5O6) EPISuite v4.0 

Vapor Pressure 5.0 x 10-6 Pa; 3.0 x 10-8 mmHg (25 °C) 

MRIDs 44024901 

44024904 

Acceptable 

Henry’s Law Constant <3.0 x 10-6 Pa m3/mol 

Aqueous Solubility 290 mg/L (25 °C; pH 6.5) 

MRIDs 44024901 

44024904 

Acceptable 

pKa

pka1 = 4.06 (basic) 

pka2 <1 (basic) 

MRIDs 44024901 

44024904 

Acceptable 

Log octanol-to-water partition coefficient 

(log KOW) -0.18 (pH ?) 

MRIDs 44024901 

44024904 

Acceptable 

MRIDs 44024901 and 44024904 provide pymetrozine solubility data for a number of common solvents. 

Environmental Fate Properties 

Environmental fate properties of pymetrozine are summarized in Table 7. These half-life values 

presented in the table have been updated from previous assessments to reflect the NAFTA 

degradation kinetics guidance9 for characterization purposes and will be used to calculate model 

input values. Updated model input values will be calculated based on current model input 

guidance for each respective exposure model at the time the assessment is completed. The 

kinetic analyses are presented in APPENDIX A. 

Table 7. Environmental Fate Parameters of Pymetrozine

Parameter Value Source

Classification; Comments

Abiotic Transformation Mechanisms

Hydrolysis half-life 

at 25 C 

12.1 days pH 5 

MRID 44024962 

(triazine ring labeled) 

supplemental 

28.4 days pH 5 

>> 30 days pH 7 

>> 30 days pH 9 

MRID 44024963 

Supplemental 

(triazine ring-labeled) 

. 

 

9 Guidance for Evaluating and Calculating Degradation Kinetics in Environmental Media, Health Canada, U.S. 

Environmental Protection Agency, December 2012. 
12 

Parameter Value Source

Classification; Comments

14.4 days pH 5 

>> 30 days pH 7 

>> 30 days pH 9 

MRID 44024964 

Supplemental 

(pyridine ring-labeled) 

Draft DER; 

MRID 44024963 

Soil photolysis half-life 

at 24 C 

13.6 d (DFOP t slow; equivalent time at 40 °N; 

dark control adjusted value) 

MRID 44411324 

Supplemental 

(pyridine ring-labeled) 

26.8 d (DFOP t slow; equivalent time at 40 °N; 

dark control adjusted value) 

MRID 44411325 

Supplemental 

(triazine ring-labeled) 

 A large amount of unextracted residues 

(>75%) was observed in the irradiated 

samples compared to the dark control 

(<20%) at study termination. 

20.2 d MRID 44411324 and MRID 44411325 

(average of the two labels) 

Aqueous photolysis 

half-life at 25 C 

3.0 d (equivalent time at 40 °N) 

MRID 44411321 

Supplemental 

(pyridine ring-labeled) 

2.0 days (equivalent time at 40 °N)

MRID 44471702 

Supplemental 

 (triazine ring-labeled) 

A major degradate (23.4% AR) was not 

identified. 

2.7 days (equivalent time at 40 °N) 

MRID 44411321 and MRID 44471702 

(combined labels; studies were conducted 

under the same conditions) 

2.0 days (reasonably representative of 40 °N )

 b

MRID 44411322 

Supplemental 

(triazine ring-labeled) 

A major degradate (28.9% AR) was not 

identified. 

Biotic Transformation Mechanismsc

Aerobic soil 

metabolism half-life at 

25 °C 

DFOP DT50= 159 d; DT90= 838 d; 

DFOP Slow t1/2 = 292 (low dose, sandy loam) 

DFOP DT50= 191 d; DT90= 824 d; 

DFOP Slow t1/2 = 381 (high dose, sandy loam)

MRID 44024965 

Supplemental 

(pyridine ring-labeled) 

 Only was soil (at a high and low dose) 

was used to assess the transformation of 

pymetrozine. Application rates used in 

this study is much higher than the 

maximum single application rate. 

96 days (low dose), 116 days (high dose) 

MRID 44024966 

Supplemental 

(triazine ring-labeled) 

Only was soil (at a high and low dose) 

was used to assess the transformation of 

pymetrozine. Application rates used in 

this study is much higher than the 

maximum single application rate. 

Anaerobic Soil 

Metabolism Half-life No data 
13 

Parameter Value Source

Classification; Comments

Aerobic Aquatic 

Metabolism Half-life No data 

Anaerobic Aquatic 

Metabolism Half-life 

half-life at 25 °C 

SFO t1/2 = 73.7 d; DT90= 245 d (low does; 

total system) 

SFO t1/2 = 83.2 d; DT90= 276 d (high does; 

total system) 

MRID 44024967 

Supplemental 

(pyridine ring-labeled) 

Formation/decline of several 

transformation products was not 

established. 

DFOP DT50= 78.5 d; DT90= 310 d; 

DFOP Slow t1/2 = 99.9 (low dose, total system)

IORE DT50= 91.1 d; DT90= 363 d; 

tR IORE = 109 d (high dose, total system) 

MRID 44024968 

Supplemental 

(triazine ring-labeled) 

Formation/decline of several 

transformation products was not 

established. 

Mobility

Range of Freundlich 

soil-water partition 

coefficients (KF); 

exponent (1/n) values; 

and 

organic carbonnormalized coefficients 

(KFOC) 

1/n <<1 

1789, 7875, 15708, 4420, 2306 MRID 44024969 (acceptable) 

Field Dissipation 

Terrestrial Field 

Dissipation Half-life 

Bareground Plot (748 g ai/A)

GA- (50WP)- t

1/2= 137 days ; DT50<3 days 

CGA-18077 (niacin) was detected 0-18 inch depth 

Parent, CGA-23199, CGA-359009, CGA-23199 were not 

detected below 0- 6inch depth 

Cotton Plot (748 g ai/A) 

GA- (50WP)- t

1/2= 122 days ; DT50 -7 and 21 days 

CGA-18077 (niacin) was detected 0-18 inch depth 

CGA-23199 was detected 0-12 inch depth 

Parent, and CGA-359009 were not detected below 0- 

6inch depth 

MRID 44647901, 44411334, 44471703, 

44647904, 44411338, 44647903 

(supplemental) 

Analytical methods were inadequate for 

detecting CGA-249257, storage stability 

for the CGA-180777, CGA-249257, and 

CGA-359009 were inadequate, 

Bareground Plot (748 g ai/A)

NY- (50WP)- t

1/2= 22 days ; DT50~3 days 

Parent was not detected below 0-6 inch depth 

CGA-249257 was detected 0-12 inch depth 

CGA-180777 was detected 0-18 inch depth 

CGA 294849 was detected 0-12 inch depth 

CGA -23199 was detected 0- 6 inch depth 

MRID 44411334 (supplemental) 

44647902 & 44647901 

Analytical methods were inadequate for 

detecting CGA-249257, storage stability 

for the CGA-180777, CGA-249257, and 

CGA-359009 were inadequate, 
14 

Parameter Value Source

Classification; Comments

Bareground Plot (748 g ai/A)

CA- (50WP)- t

1/2= 120 days 

No residues were not detected below 0- 6inch depth 

Tomato Plot (748 g ai/A) 

GA- (50WP)- t

1/2= 76 days 

No residues were not detected below 0- 6inch depth 

MRID 44411338, 44647903 

(supplemental) 

Analytical methods were inadequate for 

detecting CGA-249257, storage stability 

for the CGA-294849 and GS-23199 were 

inadequate 

Bioaccumulation 

Fish BCF 

edible, non-edible, and 

whole fish tissues 

No data 

Pymetrozine is not expected to 

bioaccumulate based on the calculated log 

Kow (-0.18). 

a. Rapid degradation of pymetrozine was observed in the dark control, which indicates photodegradation on 

soil is not a probable route of dissipation. 

b. This value is based on a 12 hour per day exposure at an average daily intensity of approximately 410 

W/m2

. No conversion factor was used to adjust to an environmentally relevant half-life. Based on the 

National Center for Atmospheric Research (NCAR)/National Center for Environmental Prediction 

(NCEP) data for June 21 (years 1948-2011) the average surface radiation at 40 °N ranges between 98-422 

W/m2

. Therefore, it is reasonable that 410 W/m2 represents a sunny day at 40 °N. 

c. Representative half-life values were calculated using the draft NAFTA degradation kinetics document: 

Guidance for Evaluating and Calculating Degradation Kinetics in Environmental Media (draft document 

June 29, 2011); Single First Order (SFO), Nth-Order Rate Model or Indeterminate Order Rate Equation 

Model (IORE), and Double First-Order in Parallel (DFOP) 

Applied Radioactivity (AR) 

BCF: bioconcentration factor 

The major route of dissipation are expected to be controlled by acid catalyzed abiotic hydrolysis, 

photodegradation in water and on soil, microbial mediated degradation in soil, and transport in 

runoff or on eroded sediment/soil. The low Henry's Law Constant value coupled with relatively 

high soil:water partitioning coefficient indicates that pymetrozine volatilization from soil is 

insignificant. The low octanol:water partition coefficient suggests that pymetrozine does not 

bioaccumulate. 

 

Transformation Products 

Fifteen degradates were observed in the pymetrozine laboratory studies: nine were identified and 

six were unknowns. The major transformation products, as well as a few minor degradates are 

listed in Table 8 with the maximum amounts of each chemical formed in the various studies. 

 
Table 8. Pymetrozine Environmental Transformation Products

Code Name/ 

Synonym 

Chemical Name/

SMILES Chemical Structure Study Type/ Conditions Ref. MRID 

Maxi

Per

App

Ra

Act

MAJOR 

CGA 215525 

4-amino-6-methyl4,5-dihydro-2H-(1,2,4)-triazin-3-one C1(NN=C(CN1N)C)=O 

HN

N

N

CH3

O

NH2

Hydrolysis 

pH 5 at 25 °C 

44024963 

(triazine 

ringlabeled) 47.8 (3

Aquatic 

Photolysis 

pH 7 at 25 °C 

44471702 

(triazine 

ringlabeled) 46.2 (3 

44411322 

(triazine 

ringlabeled) 66.0 (1

Aerobic Soil 

Metabolism 

sandy loam 

44024966 

(triazine 

ringlabeled) 7.0 (92 

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 7.2 (58 

CGA 300407 CAS Number: 500-22-1 

3-pyrideine carboxaldehyde C1=CC(=CN=C1)C=O 

O

N

Hydrolysis 

pH 5 at 25 °C 

44024964 

(pyridine 

ringlabeled) 63.0 (3

Soil Photolysis

Silt loam 

pH 7.3 

2.3% OC 

44411324 

(pyridine 

ringlabeled) 

6.13 (3

Irrad

8.96 (1

Dark C
Code Name/ 

Synonym 

Chemical Name/

SMILES Chemical Structure Study Type/ Conditions Ref. MRID 

Maxi

Per

App

Ra

Act

Aquatic 

Photolysis 

pH 7 at 25 °C 

44411321 

(pyridine 

ringlabeled) 

93.1 (3

Irrad

6.6 (30 

Dark C

CGA 3590009 

4,5-dihydro-5-hydroxy-6-methyl-4-[(3-pyridinylmethylene)amino-1,2,4-triazine-3-(2H)-one C1(NN=C(C(N1N=CC2=CN=CC=C2)O)C)=O 

HN

N

N

N

N

CH3

O

OH

Soil Photolysis

Silt loam 

pH 7.3 

2.3% OC 

44411324 

(pyridine 

ringlabeled) 

28.9 (3 

Irrad

47.4

DA

Dark C

44411325 

(triazine 

ringlabeled) 

34.22 (

Irrad

57.1

DA

Dark C

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 

1.6 (7 

total 

CGA 180777 CAS Number: 59-67-6

Niacin nicotinic acid

Pyridine-3-carboxylic acid C1=CC(=CN=C1)C(O)=O 

O

N

OH

Aquatic 

Photolysis 

pH 7 at 25 °C 

44411321 

(pyridine 

ringlabeled) 5.3 (33 

Aerobic Soil 

Metabolism 

sandy loam 

44024965 

(pyridine 

ringlabeled) 16.7 (5

Anaerobic 

Aquatic 

Metabolism 

44024967 

(pyridine 

ringlabeled) 

85.0 (35

total 
Code Name/ 

Synonym 

Chemical Name/

SMILES Chemical Structure Study Type/ Conditions Ref. MRID 

Maxi

Per

App

Ra

Act

GS 23199 

6-Methyl-2H-[1,2,4]triazine-3,5-dione C1(NC(C(=NN1)C)=O)=O 

HN

N

NH

CH3

O

O

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 

15.8 (35

total 

Aerobic Soil 

Metabolism 

sandy loam 

44024966 

(triazine 

ringlabeled) 0.9(30 

CGA 249257 

6-Methyl-4,5-dihydro-2H-[1,2,4]triazin-3-one 

C1(NCC(=NN1)C)=O 

HN

N

NH

CH3

O Aerobic Soil Metabolism 

sandy loam 

44024966 

(triazine 

ringlabeled) 0.2 (3

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 

14.1 (35

total 

MINOR

CGA 294849 

4-amino-6-methyl1,2,4-triazine3,5(2H,4H)-dione HN

N

N

CH3

O

O

NH2

Soil Photolysis

Silt loam 

pH 7.3 

2.3% OC 

44411325 

(triazine 

ringlabeled) 

5.35 (1

Irrad

5.94 (3

Dark C

Aerobic Soil 

Metabolism 

sandy loam 

44024966 

(triazine 

ringlabeled) 2.5 (30 

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 2.3 (27
Code Name/ 

Synonym 

Chemical Name/

SMILES Chemical Structure Study Type/ Conditions Ref. MRID 

Maxi

Per

App

Ra

Act

CGA 319251 

6-Oxo-1,6-dihydropyridine-3-carboxylic acid 

O NH

OH

O

Aerobic Soil 

Metabolism 

sandy loam 

44024965 

(pyridine 

ringlabeled) 

0.2 (58 

DA

CGA 313124 

6-Hydroxymethyl-4-[(pyridin-3-ylmethylene)-amino]-4,5-dihydro-2H-[1,2,4]triazin-3-one 

HN

N

N N N

H2C

O

OH

Anaerobic 

Aquatic 

Metabolism 

44024968 

(triazine 

ringlabeled) 0.5 (35

Unknown VI 

Aerobic Soil 

Metabolism 

sandy loam 

44024965 

(pyridine 

ringlabeled) 6.1 (7 

 2U 

Aerobic Soil 

Metabolism 

sandy loam 

44024966 

(triazine 

ringlabeled) 0.8 (30 

Bold font indicates the highest percentage observed for a given transformation product. MW: molecular weight AR: Applied radioactivity n.d. not detected <LOD 
19 

Mobility data have been provided for some of the identified pymetrozine transformation 

products. Select physical chemical properties of the major pymetrozine transformation products 

are provided in Table 9. Among the reported pymetrozine transformation products reported, 

CGA359009, GS23199, CW49257 and CGA180777 were detected in the field studies and 

showed some mobility. 

Table 9. Selected Physical/Chemical Parameters of Pymetrozine Environmental 

Transformation Productsa

 

Parameter 

Major Transformation Product 

CGA 

215525 

CGA 

300407 

CGA 

359009 

CGA 

180777 GS 23199 CGA 249257 

Molecular Weight (g/mol) 128.13 107.11 233.23 123.11 127.1 113.12 

Molecular Formula C4H8N4O C6H5NO C10H11N5O

2

C6H5NO2 C4H5N3O2 C4H7N3O 

Vapor Pressure (mm Hg) 2.1 x 10-5 0.568 3.1 x 10-11 9.4 x 10-5 3.2 x 10-8 2.2 x 10-4

Henry’s Constant (atm-m3/mol) 3.2 x 10-12 1.8 x 10-8 2.6 x 10-16 1.4 x 10-10 2.5 x 10-9 1.1 x 10-8

Solubility (mg/L) 79780 62860 101900 48150 4777 2931 

Log Kow -1.45 0.29 -0.65 0.36 -0.12 0.29 

Range of Freundlich soil-water 

partition coefficients (KF); 

exponent (1/n) values; and 

organic carbon-normalized 

coefficients (KFOC) 

ND 

MRID 

44411331 

ND 

MRID 

44411328 

Kf-1.4-3.3 

1/n- 0.74-.86 

KFOC- 320 

MRID 

44411326 

Kf-<0.04-0.3 

1/n- 0.89-

0.99 

KFOC-19 

MRID 

44411327 

Kf-<1.0 

1/n- 0.8-0.94 

KFOC- 168 

MRID 

44411329 

Kf-0.07-.2 

1/n- 0.53-0.83 

MRID 

44411330 

Soil Column Leaching 

a. Estimated using EPISuite v. 4 

b. ND- No data due to instability during equilibration 

Receptors 

Table 10 and Table 11 provide a summary of the aquatic and terrestrial taxonomic groups, 

respectively, and the most sensitive surrogate species tested to characterize the potential acute 

and chronic ecological effects of pymetrozine. In addition, the tables provide a preliminary 

overview of the potential acute toxicity of pymetrozine by providing the acute toxicity 

classifications. 

 
20 

 

 

Table 10. Summary of the Most Sensitive Endpoints from Aquatic Toxicity Studies for 

Pymetrozine 

Taxonomic 

Group 

Study 

Type 

Surrogate Species 

and 

Test Material 

Toxicity Value 

(all units in terms 

of measured active 

ingredient) 

MRID and 

Classification 

Acute 

Toxicity 

Classification 

Freshwater fisha

Acute 

Rainbow Trout 

(Oncorhynchus 

mykiss) 

TGAI 

LC50 > 128 mg a.i./L 

No mortality or 

sublethal effects 

reported. 

44024913 

Acceptable 

Practically 

non-toxic 

Chronic 

(Early 

Life 

Stage) 

Rainbow Trout 

(Oncorhynchus 

mykiss) 

TGAI 

NOAEC 11.7 mg 

a.i./L 

LOAEC > 11.7 mg 

a.i./L 

No mortality or 

sublethal effects 

reported. 

44024918 

Supplementalb

 -- 

Estuarine/Marine 

fish 

Acute 

Sheepshead Minnow 

(Cyprinodon 

variegatus) 

TGAI 

LC50 > 117 mg a.i./L 

No mortality or 

sublethal effects 

reported. 

44024916 

Acceptable 

Practically 

non-toxic 

Chronic No Data 

Freshwater 

invertebrates 

Acute 

Water Flea 

(Daphnia magna) 

TGAI 

EC50= 87 mg a.i./L 

NOAEC= <19.2 mg 

a.i./L 

Sublethal signs of 

toxicity (less active 

than controls) were 

reported at all test 

concentrations. 

44024914 

Acceptable Slightly toxic 

Chronic 

Water Flea 

(Daphnia magna) 

TGAI 

NOAEC = 0.025 

mg a.i./L 

LOAEC = 0.052 mg 

a.i./L 

Most sensitive 

endpoint: 

Reproduction and 

growth 

44024919 

Acceptable -- 

 
21 

Estuarine/Marine 

invertebrates 

Acute 

Eastern Oyster 

(Crassostrea 

virginicia) 

TGAI 

LC50 = 3.05 mg 

a.i./L 

NOAEC = 0.768 mg 

a.i./L 

No sublethal effects 

were observed 

44024917 

Acceptable 

Moderately 

toxic 

Chronic No Data 

Aquatic plants 

and algae 

Nonvascular 

Green algae 

(Pseudokirchneriella 

subcapitata) 

TGAI 

EC50= 17 mg a.i./L 

NOAEC = 6.28 mg 

a.i./L based on a 

reduction in cell 

density 

44024959 

Acceptable -- 

Vascular 

Duckweed 

 (Lemna gibba) 

TGAI 

EC50 >109 mg a.i./L 

NOAEC = 49 mg 

a.i./L based on a 

reduction in frond 

number 

44024960 

Supplementalc -- 

a. Freshwater fish represent surrogates for aquatic-phase amphibians. 

b. Classified as supplemental because the solvent concentration used exceeded the guideline recommendations and 

the highest tested concentration (only up to 13 mg a.i./L) was not high enough to produce adverse effects. 

However, this study is considered acceptable for quantitative use because 13 mg a.i./L is much higher than the 

expected environmental concentrations. 

c. Classified as supplemental because the test material was unstable in solution as the treatment solutions did not 

contain detectable amounts at test termination. The EC50 is based on the initial measured concentration rather 

than the mean. As a result, the toxicity may be underestimated, however, given that the EECs from previous 

assessments were well below the NOAEC (the RQ would be 0.001), these supplemental data are acceptable for 

use in risk assessment. 

 
22 

Table 11. Summary of the Most Sensitive Endpoints from Terrestrial Toxicity Studies for 

Pymetrozine 

Taxonomic 

Group 

Study 

Type 

Surrogate Species 

and 

Test Material 

Toxicity Value 

(all units in terms of 

measured active 

ingredient) 

MRID and 

Classification 

Acute 

Toxicity 

Classification 

Birdsa

Acute 

Bobwhite quail 

(Colinus 

virginianus) 

TGAI 

LD50 >2000 mg/kg-bw 

No mortality reported. 

Sublethal effects 

(subdued behavior, 

unsteadiness and 

prostrate posture) were 

noted in all three 

treatment levels-effects 

subside by the beginning 

of day 3. The resulting 

NOAEC is <500 mg/kgbw based on sublethal 

effects. 

44024908 

Acceptable 

Practically 

non-toxic 

Sub-acute 

dietary 

Mallard 

(Anas 

platyrhynchos) 

TGAI 

LC50 >5010 

mg/kg diet 

No mortality reported. 

NOAEC=311 mg a.i./kg 

diet based on reduced 

body weight gain at the 

650, 1300, 2600, and 

5200 mg/kg diet dose 

levels. 

440224910 

Acceptable 

Practically 

non-toxic

Chronic 

Bobwhite quail 

(Colinus 

virginianus) 

TGAI 

NOAEC = 100 mg 

a.i./kg 

LOAEC = 300 mg 

a.i./kg based on number 

of 14-day old survivors 

of eggs set 

44024911 

Acceptable -- 

Mammals 

Acute Oral 

Laboratory rat 

(Rattus 

norvegicus) 

LD50 = 5955 mg a.i./kgbw 

44024926 

Acceptable 

Practically 

non-toxic 

Acute 

Inhalation 

Laboratory rat 

(Rattus 

norvegicus) 

LC50 = 1.8 mg a.i./L 44024930 

Acceptable -- 

Chronic 

Laboratory rat 

(Rattus 

norvegicus) 

NOAEC = 200 mg 

a.i./kg diet (NOAEL= 

13.9 mg/kg-bw/day) 

LOAEC = 2000 mg 

a.i./kg based on reduced 

body weight in 

offspring. 

No effects on 

reproduction. 

44024950 

Acceptable --
23 

Taxonomic 

Group 

Study 

Type 

Surrogate Species 

and 

Test Material 

Toxicity Value 

(all units in terms of 

measured active 

ingredient) 

MRID and 

Classification 

Acute 

Toxicity 

Classification 

Insects 

Acute 

contact 

Honey bee 

(Apis mellifera L.) 

TGAI 

LD50 >200 μg a.i./bee 

NOAEL= 200 μg 

a.i./bee 

No sublethal effects. 

44024961 

 Acceptable 

Practically 

non-toxic

Acute Oral 

Honey bee 

(Apis mellifera L.) 

TGAI 

LD50 >117 μg a.i./bee 

NOAEC= Not 

determined. 

Signs of toxicity noted at 

all exposure levels 

included uncoordinated 

movements, and lying on 

sides and backs. These 

signs were noted within 

1 hour of dosing but 

were absent by 24 hours. 

Practically 

non-toxic 

a. Birds represent surrogates for terrestrial-phase amphibians and reptiles.

Ecological Effects Characterization 

On an acute exposure basis, pymetrozine is classified as “practically non-toxic” to freshwater 

and estuarine/marine fish, “slightly toxic” to freshwater invertebrates, and “moderately toxic” to 

estuarine/marine invertebrates. On a chronic exposure basis, based on a supplemental study for 

freshwater fish (rainbow trout- Oncorhynchus mykiss), there were no effects reported up through 

the highest test concentration, resulting in a NOAEC of 11.7 mg a.i./L. For freshwater 

invertebrates, a study with the water flea (Daphnia magna), resulted in a NOAEC of 0.025 mg 

a.i./L based on reduced reproduction and growth (compared to the control). Chronic toxicity 

data are not available for estuarine/marine fish or invertebrates. For vascular aquatic plants, the 

EC50 for duckweed (Lemna gibba) is >109 mg a.i./L with a NOAEC of 49 mg a.i./L (there was 

41% inhibition in frond number at the highest dose of 109 mg a.i./L). For non-vascular plants, 

the EC50 is 17 mg a.i./L for green algae (Pseudokirchneriella subcapitata) with a NOAEC of 

6.28 mg a.i./L based on reduced cell density. In previous assessments, there were no LOC 

exceedances/risk concerns for aquatic animals and plants from acute or chronic exposure to 

pymetrozine. 

Based on the available data, pymetrozine is classified as “practically non-toxic” to birds on an 

acute and subacute exposure basis; however, there is uncertainty with this classification because 

acceptable data are only available for one species in the acute oral study and in the dietary study, 

there was reduced body weight gain at the 650, 1300, 2600, and 5200 mg/kg diet dose levels. On 

a chronic exposure basis, the NOAEC for the bobwhite quail is 100 mg a.i./kg diet, based on a 

reduction in the number of 14-day survivors of eggs set. For mammals, pymetrozine is classified 

as “practically non-toxic” on an acute exposure basis. On a chronic exposure basis, the NOAEC 

for the rat (Rattus norvegicus) is 200 mg a.i./kg diet (NOAEL= 13.9 mg/kg-bw/day) based on 

reduced body weight in offspring. Based on the available data for the honey bee (Apis mellifera 

L.), pymetrozine is classified as “practically non-toxic” with LD50 values of >117 and >200 μg 

a.i./bee, for acute oral and contact, respectively, however, there is uncertainty with the available 
24 

data (see discussion in Data Gaps). Toxicity data are not available for terrestrial plants. Based on 

available data in previous assessments, risks were only identified for mammals on a chronic 

exposure basis. 

Based on the available acute oral study (MRID 44024961), there were several signs of toxicity 

(including uncoordinated movements and bees lying on their sides and backs) noted at all 

exposure levels suggesting that the mode of action may extend beyond inhibition of feeding 

behavior. A more recent acute oral/contact study (MRID 45579702) is available and while it has 

not been fully reviewed at this time, a preliminary review of the data shows that when bees were 

exposed (oral) and observed for a longer duration (6 hours and 96 hours, respectively), that while 

mortality was low (a similar observation to the earlier study), bees at the three highest treatments 

(1.01, 8.77, and 62.71 μg a.i./bee) exhibited sublethal effects (e.g., bees showing symptoms of 

paralysis/restricted movement of legs) at 24 hours after treatment in 90% of the bees, and by the 

end of the study the bees were only partially recovered with 57.5%, 30%, and 10% healthy in the 

1.0, 8.77, and 62.7 μg a.i./bee treatments, respectively. In this same study, a significant reduction 

in feeding was also observed at the 0.12, 1.01, 8.77, and 62.71 μg a.i./bee treatment levels when 

compared to the control (MRID 45579702). Finally, there are two field studies (141-2, honey 

bee residue on foliage; MRIDs 44024961 and 45579702) that have not been fully reviewed but 

both studies reported an increase in honey bee mortality and reduced foraging activity when 

compared to the control or pre-exposure period. While it is noted that MRIDs 45579702, 

44024961, and 45579702 require further review (which will be completed prior to the risk 

assessment) the information in these studies along with the data in the acceptable study provide a 

weight of evidence that exposure to pymetrozine might adversely affect bees. Because sublethal 

effects were observed in 90% of the bees at the three highest treatments at 24 hours after 

treatment, and those effects persisted (up to 90% in the highest treatment group) throughout the 

study (96 hours), the 96-hour observation duration may not fully capture the extent of the effects 

(e.g., cessation of feeding, decreasing recovery, or mortality). Therefore, additional data are 

needed to fully understand the level of risk that pymetrozine can pose to the honey bee. 

Ecological Incidents 

As of January 29, 2013, no incidents were reported in the Ecological Incident Information 

System (EIIS, version 2.1- maintained by the EPA), the Avian Monitoring Information System 

(AIMS- maintained by the American Bird Conservancy), or in the IDS Aggregate Incident 

Reports’ Database (maintained by the EPA). 

Conceptual Model 

The environmental fate properties of pymetrozine indicate that direct spray, spray drift, and 

runoff (either via dissolved phase or particle transport of sorbed pymetrozine) represent potential 

transport mechanisms. These pathways may result in a wide range of potential aquatic and 

terrestrial exposure scenarios to both pymetrozine as well as its environmental transformation 

products. 

 
25 

Analysis Plan 

Stressors of Concern 

Drinking Water Exposure Assessment 

The major degradate, CGA359009 is currently considered a residue of concern in drinking 

water8

; however, if any additional environmental transformation products of pymetrozine 

identified as a potential toxicological concern with similar toxicity as the parent will be 

considered using a total toxic residue (TTR) approach. 

Ecological Risk Assessment 

In order to address the risk hypothesis, the potential for adverse effects on the environment will 

be estimated. The use, environmental fate, and ecological effects of pymetrozine and its 

degradation products will be characterized and integrated to assess the overall risks. There are a 

total of six major degradation products (CGA-359009, CGA 215525, GS 23199, CGA 249257, 

CGA 300407, and CGA 180777). Toxicity data are not available for these degradation products. 

Additionally, a query of the European Pesticide Properties Database (PPDB)10 did not show any 

studies submitted for the degradation products. In order to gain an understanding of the potential 

toxicity of the degradates, a structure activity analysis using ECOSAR (V1.1) was conducted. 

Based on the ECOSAR output, five of the six degradates [(CGA-359009, CGA 215525, GS 

23199 and CGA 249257 predicted with the “hydrazine training set”); CGA 300407-predicted 

with the “aldehydes” training set] are estimated to exhibit approximately equal toxicity to 

pymetrozine (See APPENDIX F for the ECOSAR input and output). The last degradate, CGA 

180777, is estimated to be less toxic and is also only formed under anaerobic aquatic conditions, 

therefore , this degradate will not be considered as a residue of concern. 

A total toxic residue approach will be used to assess the exposure to pymetrozine (FIFRA SAP, 

2008), thus, this assessment will assume that the toxicity of the degradation products (CGA359009, CGA 215525, GS 23199, CGA 249257, and CGA 300407) are equivalent to 

pymetrozine. Risk quotients (RQs) will be derived for total toxic residues (pymetrozine and the 

degradates listed above) by dividing estimated environmental concentrations (EECs) by the most 

sensitive endpoint from the relevant, available toxicity data for pymetrozine. 

Measures of Exposure 

EFED will use standard available models to evaluate potential exposures to aquatic and 

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

The models used to generate aquatic estimated environmental concentrations (EEC) are the 

Pesticide Root Zone Model (PRZM) coupled with the EXposure Analysis Model System 

 

10 PPDB. Pesticide Properties Database. Universityof Hertfordshire. 

http://sitem.herts.ac.uk/aeru/footprint/index2.htm
26 

(EXAMS). Model input values will be consistent with the most recent version of the Input 

Parameter guidance (current version 2.1; USEPA 2009). The model used to produce terrestrial 

EECs on food items is T-REX. Using the TREX model, we will assume that the default half-life 

value of 35 days for foliar residue dissipation will capture the parent and degradates, unless data 

becomes available to suggest that the 35-day half-life is inadequate. Given that pymetrozine is 

systemic, there will be additional uncertainty associated with the TREX estimates of the EECs. 

The model used to derive EECs relevant to terrestrial and wetland plants is TerrPlant. The 

AgDRIFT spray drift model (v2.01; May 2001) is used to assess exposures of organisms to 

bifenazate deposited on terrestrial or aquatic habitats by spray drift. These models are 

parameterized using relevant reviewed registrant-submitted environmental fate data. Because 

pymetrozine and its degradation product (CGA-359009) are assumed to have similar toxicity to 

terrestrial and aquatic organisms, a total toxic residues approach will be used in the exposure 

modeling (FIFRA SAP, 2008). The predicted estimated environmental concentrations of total 

toxic residues (pymetrozine and CGA-359009) will be used to calculate risk quotients. 

For problem formulation, screens were conducted for the potential exposure from drinking water 

and inhalation. For drinking water, the Screening Imbibition Program (SIP v. 1.0, Released June 

15, 2010)11 was used to calculate an upper bound estimate of exposure. Exposure from drinking 

water alone was determined to be a potential pathway of concern for avian and mammalian 

species on a chronic exposure basis. On an acute exposure basis, drinking water alone was not a 

concern for mammals and while there is a potential concern for birds identified there is also 

uncertainty because the toxicity value was non-definitive (i.e. the LD50 >2000 mg/kg-bw) and the 

value of 2000 mg/kg-bw was used in the model as an upperbound estimate (APPENDIX B). 

Additionally, this modeling does not take into account that drinking water may contribute to a 

total exposure that has the potential for effects on non-target animals when aggregated with other 

exposure pathways (dietary food sources, dermal, inhalation). Because there is a high degree of 

conservatism in the SIP 1.0 exposure estimate, there is limited expectation that use scenarios not 

triggering a SIP 1.0 concern would contribute significantly to aggregate risks from water plus 

diet when a refined water exposure model is incorporated in the actual quantitative risk 

assessment. 

The Screening Tool for Inhalation Risk (STIR v.1.0, November 19, 2010)12 was used to calculate 

an upper bound estimate of exposure from inhalation. Based on the results of the STIR model, 

inhalation exposure alone was not determined to be a potential pathway of concern for avian or 

mammalian species on an acute basis (APPENDIX C). Inhalation exposure via spray drift 

and/or the vapor-phase of the pesticide alone does not appear to be of concern. The analysis of 

the inhalation route in STIR does not consider that aggregation with other exposure pathways 

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

for effects to non-target animals. However, the Agency does consider the relative importance of 

other routes of exposure in situations where data indicate that pesticide exposures through other 

routes may be potentially significant contributors to wildlife risk (USEPA, 2004). The risk 

 

11 Detailed information about SIP v. 1.0, as well as the tool, can be found on the EPA’s website at 

http://www.epa.gov/pesticides/science/models_pg.htm#terrestrial. 

12 Detailed information about STIR v.1.0, as well as the tool, can be found on the EPA’s website at: 

http://www.epa.gov/pesticides/science/models_pg.htm#terrestrial. 
27 

characterization section will discusses the impact of the consideration of other routes of exposure 

that have been identified as potentially important, and the degree of certainty associated with 

screening-level risk assessment conclusions. 

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 are 

identified using EPA’s ECOTOXicology database (ECOTOX) (USEPA, 2007c), which employs 

a literature search engine for locating chemical toxicity data for aquatic life, terrestrial plants, 

and wildlife. 

Endangered Species Assessments 

Consistent with the Agency’s responsibility under the Endangered Species Act (ESA), the 

Agency will evaluate risks to federally listed threatened and/or endangered species (“listed 

species”) from registered uses of pesticides in registration review. These assessments will be 

conducted in accordance with standard EPA procedures and good scientific judgment. The 

process for evaluating potential risks to listed species is further described at 

http://www.epa.gov/oppfead1/endanger/litstatus/riskasses.htm. 

Endocrine Disruptor Screening Program 

Pymetrozine is not included in the first group of 67 chemicals issued an order to conduct Tier 1 

EDSP testing. For additional information on the EDSP program, visit 

http://www.epa.gov/endo/. 
28 

Preliminary Identification of Data Gaps 

Environmental Fate 

Table 12 identifies the environmental fate studies submitted by the registrant, as well as study 

classifications and whether or not additional data are needed in order to support the registration 

review exposure assessments. Rationale for the additional data requested is also presented. 

Table 12. Status of Environmental Fate Data for Pymetrozine 

OCSPP 

Guideline 

Data 

Requirement 

Submitted 

Studies 

(MRID) 

Study 

Classifications

Are data 

needed to 

conduct risk 

assessment?

Comments 

835.2120 Hydrolysis 

44024962 

44024963 

44024964 

Supplemental 

Supplemental 

Supplemental 

Yes 

Results are not consistent between 

hydrolysis studies (MRIDs 44024964 

and 44024963) for pH 5, with half-lives 

ranging from 12 to 28 days. Because 

hydrolysis appears to an important route 

of dissipation in acidic environments, 

additional abiotic hydrolysis data for 

pH 5 are needed. 

835.2240 Aqueous 

Photolysis 

44411321 

44471702 

44411322 

Supplemental 

Supplemental 

Supplemental 

Noa 

A major degradate (up to 28.9% AR) 

was not identified. 

Identification of this transformation 

product is needed to rule out the 

potential that it is a residue of 

toxicological concern. In absence of the 

data, this residue may be considered as 

part of a TTR approach in modeling to 

account for this uncertainty. 

835.2410 Soil Photolysis 44411324 

44411325 

Supplemental 

Supplemental Noa

 A large amount of unextracted residues 

(>75%) was observed in the irradiated 

samples compared to the dark control 

(<20%) at study termination. 

835.4100 Aerobic Soil 

Metabolism 

44024965 

44024966 

Supplemental 

Supplemental Noa

Current guidelines recommend aerobic 

soil metabolism data be submitted for a 

total of five different soils. In absence of 

this data the calculated aerobic soil 

metabolism half-life value will be 

multiplied by 3 to generate model input 

values. This adjustment factor is applied 

to account for the uncertainty associated 

with the variation in transformation in 

different soil systems. 

835.4200 Anaerobic Soil 

Metabolism No data Noa Results from the anaerobic aquatic 

metabolism study will be used. 
29 

835.4300 Aerobic Aquatic 

Metabolism No data Yesa

These data have not been submitted to 

the EPA. 

In absence of this data the calculated 

aerobic soil metabolism half-life input 

values will be multiplied by 2 (6 times 

the aerobic soil metabolism half-life 

values) to generate model input value 

for aerobic aquatic metabolism. This 

adjustment factor is applied to account 

for the uncertainty associated with the 

different between aerobic soil and 

aerobic aquatic metabolism. 

835.4400 

Anaerobic 

Aquatic 

Metabolism 

44024967 

44024968 

Supplemental 

Supplemental No 

Current guidelines recommend 

anaerobic aquatic metabolism data be 

submitted for a total of two different 

sediment:water systems. 

835.1230 

835.1240 

Adsorption/ 

desorption and 

leaching 

44024969 Acceptable No 

835.1410 Volatility – 

laboratory No data Noa

Pymetrozine is not expected to volatilize

based on the reported vapor pressure 

and Henry’s Law Constant. 

850.6100 

Terrestrial field 

dissipation 

44411334 

44647901 

Supplemental 

Yes 

Storage stability for the CGA-180777, 

CGA-249257, and CGA-359009 were 

inadequate. Because CGA-359009 is 

one of the identified residues of concern, 

submission of storage stability studies 

are needed. 

44647903 

44411338 

Supplemental 

44471703 Supplemental 

Analytical 

method 

in soil 

44647902 Supplemental No Analytical methods were inadequate for 

detecting CGA-249257 44411333 

44411337 

Supplemental 

44411339 

44411332 

Supplemental 

Analytical 

method in water 

Not applicable No direct application to aquatic 

environments 

850.1730 Fish 

bioconcentration No data noa

Pymetrozine is not expected to 

bioaccumulate based on the calculated 

log Kow (-0.18). 

a. Additional data would reduce uncertainty. See comments. 
30 

Ecological Effects Data Gaps 

Acceptable acute avian oral toxicity data for pymetrozine are available for the bobwhite 

quail. The acute oral study conducted with the mallard duck is classified as supplemental 

and is not suitable for use in risk assessment due to regurgitation that occurred in the three 

highest test concentrations. Additionally, data are not available for passerines, which are 

required under the 40 CFR Part 158 (Oct. 26, 2007) data requirements for conventional 

pesticides (72 FR 60934; USEPA 2007a). The Part 158 data requirements specify that acute 

avian oral toxicity data be submitted for either a mallard duck or bobwhite quail, and for a 

passerine species. Therefore, an avian oral toxicity test conducted with a passerine (OCSPP 

Guideline 850.2100) is needed. EFED recommends that a passerine study protocol be 

submitted for review by the Agency prior to initiation of this study. 

Terrestrial plant toxicity studies are needed to understand the effects of pymetrozine to nontarget plants. Given that pymetrozine is systemic in plants and that toxic effects were 

observed in the aquatic plants that were tested, EFED recommends that the Seedling 

Emergence and Seedling Growth and Vegetative Vigor toxicity tests (OCSPP Guidelines 

850.4100 and 850.4150) toxicity tests are conducted. 

The available data for the honey bee (Apis mellifera L.) is considered acceptable; however, 

the study duration for the acute oral test was only for 48 hours. While 48 hours is considered 

an acceptable period of time according to the guideline, in the case of pymetrozine there is 

uncertainty when considering that the mode of action can take several days before mortality 

occurs (as seen with the target pests). Additionally, based on the available acute oral study 

(MRID 44024961), there were several signs of toxicity (including uncoordinated movements 

and bees lying on their sides and backs) noted at all exposure levels suggesting that the mode 

of action may extend beyond inhibition of feeding behavior. A preliminary review of a more 

recent acute oral/contact study (MRID 45579702) shows that when bees were exposed (oral) 

and observed for a longer duration (6 hours and 96 hours, respectively), that while mortality 

was low (a similar observation to the earlier study), bees at the three highest treatments (1.01, 

8.77, and 62.71 μg a.i./bee) exhibited sublethal effects (e.g., bees showing symptoms of 

paralysis/restricted movement of legs) at 24 hours after treatment in 90% of the bees, and by 

the end of the study the bees were only partially recovered with 57.5%, 30%, and 10% 

healthy in the 1.0, 8.77, and 62.7 μg a.i./bee treatments, respectively. In this same study, a 

significant reduction in feeding was also observed at the 0.12, 1.01, 8.77, and 62.71 μg 

a.i./bee treatment levels when compared to the control (MRID 45579702). Finally, there are 

two field studies (141-2-Honey bee residue on foliage; MRIDs 44024961 and 45579702) that 

reported an increase in honey bee mortality and reduced foraging activity when compared to 

the control or pre-exposure period. While it is noted that MRIDs 45579702, 44024961, and 

45579702 require further review (which will be completed prior to the risk assessment) the 

information in these studies along with the data in the acceptable study provide a weight of 

evidence that exposure to pymetrozine might adversely affect bees. Because sublethal effects 

were observed in 90% of the bees at the three highest treatments at 24 hours after treatment, 

and those effects persisted (up to 90% in the highest treatment group) throughout the study 

(96 hours), the 96-hour observation duration may not fully capture the extent of the effects 

(e.g., cessation of feeding, decreasing recovery, or mortality). Therefore, EFED recommends 
31 

the submission of an OECD semi-field toxicity study (see data rationale below) to fully 

understand the level of risk that pymetrozine can pose to the honey bee. An acute oral and 

contact toxicity study (OCSPP Guideline 850.3020) with a longer exposure period (e.g., ≥ 6 

hours) and also an observation period that is long enough to determine the fate (recovery or 

mortality) of the bees exhibiting sublethal effects is recommended to reduce the current 

uncertainty with the available data. 

OECD Guideline 75: Honey bee (Apis mellifera L.) Brood Test under Semi-field 

Conditions: realistic exposures and effects on various measures of brood development 

and bee health. This study also provides measures of residue in pollen and nectar. Bee 

bread can be spiked and exposure to test material assured. Available studies provide a 

weight of evidence that indicates exposure to pymetrozine might adversely affect bees. 

Because sublethal effects were observed in 90% of the bees at the three highest 

treatments at 24 hours after treatment, and those effects persisted (up to 90% in the 

highest treatment group) throughout the study (96 hours), the 96-hour observation 

duration may not fully capture the extent of the effects (e.g., cessation of feeding, 

decreasing recovery, or mortality). EFED recommends that the observation period of 

exposed honey bees be extended to 14-days to capture the full potential of effects due to 

exposure to pymetrozine residues. EFED recommends that a proposed protocol be 

submitted prior to initiation of the study. 

Table 13 provides a summary of the status of effects data for Pymetrozine.

Table 13. Status of Environmental Ecological Toxicity Fate Data for Pymetrozine 

Guideline 

Number Data Requirement

Submitted 

Studies 

MRID 

Number

Study 

Classifications

Are data 

needed for 

risk 

assessment?

Comments 

850.2100 

Avian acute oral LD50

(bobwhite quail) 

(mallard duck) 

44024908 

44024907 Acceptable 

Supplemental 

Yes 

Currently there is a data gap 

because acceptable data are 

only available for one 

species. The supplemental 

study with the mallard is 

not acceptable for 

quantitative use in risk 

assessments. Therefore, 

data are needed on a 

passerine species to get a 

better understanding of 

species sensitivity to 

pymetrozine. 

850-2200 

Avian subacute dietary LC50

(mallard duck) 

(bobwhite quail) 

44024910 

44024909 

Acceptable 

Supplemental 

No 
32 

850-2300 

Avian reproduction 

(bobwhite quail) 

(mallard duck) 

 (mallard duck) 

44024911 

44411304 

46276601 

Acceptable 

Supplemental 

Supplemental 

No 

850-1075 

Freshwater fish acute LC50

 (rainbow trout) 

(bluegill sunfish) 

44024913 

44024912 

Acceptable 

Acceptable No 

850-1300 

Freshwater invertebrate acute 

EC50

(daphnia) 

44024914 Acceptable No 

850-1075 Estuarine/marine fish acute LC50

(sheepshead minnow) 44024916 Acceptable No 

850-

1025;1035 

Estuarine/marine invertebrate 

acute EC50

(eastern oyster) 

(mysid) 

44024917 

44024915 

Acceptable 

Supplemental 

No 

850-1400 

Freshwater fish early life stage 

(rainbow trout) 44024918 Supplemental No 

Classified as supplemental 

because the solvent 

concentration used 

exceeded the guideline 

recommendations and the 

highest tested concentration 

(only up to 13 mg a.i./L) 

was not high enough to 

produce adverse effects. 

However, this study is 

considered acceptable for 

quantitative use because 13 

mg a.i./L is much higher 

than the expected 

environmental 

concentrations. 

850-1300 Freshwater invertebrate life 

cycle (daphnia) 

 

44024919 Acceptable No 

850-1400 Estuarine/marine fish life cycle 

(sheepshead minnow) No study -- No 

Due to the general low 

toxicity to fish, the value of 

this data to the ecological 

risk assessment is low. The 

chronic freshwater data will 

serve as a surrogate given 

the similarity in the acute 

toxicity values. 
33 

850-1350 Estuarine/marine invertebrate 

life cycle (mysid) No study -- No 

Due to the general low 

toxicity to aquatic 

invertebrates , the value of 

this data to the ecological 

risk assessment is low. The 

chronic freshwater data will 

serve as a surrogate given 

the similarity in the acute 

toxicity values of the 

freshwater daphnid and the 

saltwater mysid. 

850-1500 Freshwater fish full life cycle No study -- No 

Due to the general low 

toxicity to fish on a chronic 

exposure basis, the value of 

this data to the ecological 

risk assessment is low. 

850-1950 Aquatic Field Study No study -- No 

81-1 Acute mammalian oral LD50 

(rat) 44024926 Acceptable No 

81-3 Mammalian Inhalation 

(rat) 44024930 Acceptable No 

83-4 Mammalian Reproduction 

(rat) 44024950 Acceptable No 

850-4100 Seedling Emergence and 

Seedling Growth No study -- Yes 

A study is needed to 

understand the effects of 

pymetrozine to non-target 

plants. Given that 

pymetrozine is systemic in 

plants and that toxic effects 

were observed in the 

aquatic plants that were 

tested, toxicity data are 

necessary for ecological 

risk assessment. 

850-4150 Vegetative Vigor No study -- Yes 

A study is needed to 

understand the effects of 

pymetrozine to non-target 

plants. Given that 

pymetrozine is systemic in 

plants and that toxic effects 

were observed in the 

aquatic plants that were 

tested, toxicity data are 

necessary for ecological 

risk assessment. 

850-4500 

850.4550 

Aquatic plant algae 

(green algae) 44024959 Acceptable No 

Only one species was tested 

rather than four, however, 

given that the EECs from 

previous assessments were 

well below the NOAEC 

(the RQ would be <0.01), 

the value of additional data 

is low. 
34 

850-4400 Aquatic plant acute EC50

(duckweed) 44024960 Supplemental No 

This study was classified as 

supplemental because the 

test material was unstable 

in solution and the EC50 is 

based on the initial 

measured concentration 

rather than the mean 

measured concentration. As 

a result, the toxicity may be 

underestimated, however, 

given that the EECs from 

previous assessments were 

well below the NOAEC 

(the RQ would be 0.001), 

additional data are not 

needed at this time. 

850-3020/ 

Nonguideline 

Acute honey bee contact LD50

Acute honey bee oral LD50/

44024961 

45579702 

Acceptable 

In review 

No 

Nonguideline 

OECD Guideline 75: Honey bee 

Brood Test Under Semi-field 

Conditions 

(Semi-field Toxicity Study) 

No study -- Yes 

Additional data are needed 

to fully understand the level 

of risk pymetrozine poses 

to the honey bee (see 

discussion and rationale 

above). A proposed 

protocol should be 

submitted for review and 

approval. 

850-3030 Honey Bee Residue on Foliage 45579701 

45579703 In review No 

850-3040 Honey Bee Field Testing for 

Pollinator No study -- No 

Appendices

– APPENDIX A. Environmental Fate Kinetic Analyses 

– Appendix B. Results of SIP 

– Appendix C. Results of STIR 

– Appendix D. Ecological Effects Bibliography 

– Appendix E. Environmental Fate Bibliography 

– Appendix F. ECOSAR Results 

 
35 

APPENDIX A 

Environmental Fate Kinetic Analyses

Hydrolysis 
36 

 
37 

Aquatic Photolysis 

 
38 

Soil Photolysis 
39 

 
40 

APPENDIX B 

Results of SIP

 

 

Parameter Value 

Chemical name Pymetrozine 

Solubility (in water at 25oC; mg/L) 290 

 

Mammalian LD50 (mg/kg-bw) 5955 

Mammalian test species laboratory rat 

Body weight (g) of "other" mammalian species 

 

Mammalian NOAEL (mg/kg-bw) 13.9 

Mammalian test species laboratory rat 

Body weight (g) of "other" mammalian species 

 

Avian LD50 (mg/kg-bw) 2000 

Avian test species northern bobwhite quail 

Body weight (g) of "other" avian species 

Mineau scaling factor 1.15 

 

Mallard NOAEC (mg/kg-diet) 0 

Bobwhite quail NOAEC (mg/kg-diet) 100 

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) 49.8800 49.8800 

Adjusted toxicity value (mg/kg-bw) 4580.3512 10.6913 

Ratio of exposure to toxicity 0.0109 4.6655 

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) 234.9000 234.9000 

Adjusted toxicity value (mg/kg-bw) 1440.8590 10.6298 

Ratio of exposure to acute toxicity 0.1630 22.0982 

Conclusion* 

Exposure through drinking 

water alone is 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. 
41 

APPENDIX C 

Results of STIR 

Input 

Application and Chemical Information 

Enter Chemical Name Pymetrozine 

Enter Chemical Use Ornamental/Xmas 

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) 217.2 

Enter Chemical Vapor Pressure (mmHg) 3.00E-08 

Enter Application Rate (lb a.i./acre) 0.3125 

 

Toxicity Properties 

Bird 

Enter Lowest Bird Oral LD50 (mg/kg bw) 2000 

Enter Mineau Scaling Factor 1.15 

Enter Tested Bird Weight (kg) 0.178 

Mammal 

Enter Lowest Rat Oral LD50 (mg/kg bw) 5955 

Enter Lowest Rat Inhalation LC50 (mg/L) 1.8 

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/m3) 3.51E-04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 4.41E-05 

Adjusted Inhalation LD50 3.37E+00 

Ratio of Vapor Dose to Adjusted Inhalation LD50 1.31E-05 

Exposure not Likely 

Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 3.30E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 9.80E-03 

Exposure not Likely 

Significant 

 

Results Mammalian (0.015 kg ) 

Maximum Vapor Concentration in Air at Saturation (mg/m3) 3.51E-04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 5.54E-05 

Adjusted Inhalation LD50 1.07E+02 

Ratio of Vapor Dose to Adjusted Inhalation LD50 5.17E-07 

Exposure not Likely 

Significant 

Maximum Post-treatment Spray Inhalation Dose (mg/kg) 4.15E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation LD50 3.87E-04 

Exposure not Likely 

Significant 

Input 
42 

Application and Chemical Information 

Enter Chemical Name Pymetrozine 

Enter Chemical Use Potatoes 

Is the Application a Spray? (enter y or n) y 

If Spray What Type (enter ground or air) air 

Enter Chemical Molecular Weight (g/mole) 217.2 

Enter Chemical Vapor Pressure (mmHg) 3.00E-08 

Enter Application Rate (lb a.i./acre) 0.1719 

 

Toxicity Properties 

Bird 

Enter Lowest Bird Oral LD50 (mg/kg bw) 2000 

Enter Mineau Scaling Factor 1.15 

Enter Tested Bird Weight (kg) 0.178 

Mammal 

Enter Lowest Rat Oral LD50 (mg/kg bw) 5955 

Enter Lowest Rat Inhalation LC50 (mg/L) 1.8 

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/m3) 3.51E-04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 4.41E-05 

Adjusted Inhalation LD50 3.37E+00 

Ratio of Vapor Dose to Adjusted Inhalation LD50 1.31E-05 Exposure not Likely Significant 

Maximum Post-treatment Spray Inhalation Dose 

(mg/kg) 1.65E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 4.90E-03 Exposure not Likely Significant 

 

Results Mammalian (0.015 kg ) 

Maximum Vapor Concentration in Air at Saturation 

(mg/m3) 3.51E-04 

Maximum 1-hour Vapor Inhalation Dose (mg/kg) 5.54E-05 

Adjusted Inhalation LD50 1.07E+02 

Ratio of Vapor Dose to Adjusted Inhalation LD50 5.17E-07 Exposure not Likely Significant 

Maximum Post-treatment Spray Inhalation Dose 

(mg/kg) 2.08E-02 

Ratio of Droplet Inhalation Dose to Adjusted Inhalation 

LD50 1.94E-04 Exposure not Likely Significant 

 
43 

APPENDIX D 

Ecological Effects Bibliography

Avian Single Dose Oral Toxicity 

44024907 Hakin, B. (1993) CGA-215944: Acute Oral Toxicity (LD50) to Mallard Duck: Lab 

Project Number: CBG 560/921044: 478-92. Unpublished study prepared by 

Huntingdon Research Centre, Ltd. 46 p. 

44024908 Hakin, B. (1993) CGA-215944: Acute Oral Toxicity (LD50) to Bobwhite Quail: Lab 

Project Number: CBG 559/921043: 477-92. Unpublished study prepared by 

Huntingdon Research Centre, Ltd. 42 p. 

Avian Dietary Toxicity 

44024909 Hakin, B. (1992) CGA-215944: Sub-Acute Dietary Toxicity (LC50) to Bobwhite 

Quail: Lab Project Number: CBG 557/920414: 475-92. Unpublished study prepared 

by Huntingdon Research Centre, Ltd. 36 p. 

44024910 Hakin, B. (1992) CGA-215944: Sub-Acute Dietary Toxicity (LC50) to Mallard 

Duck: Lab Project Number: CBG 558/920382: 476-92. Unpublished study prepared 

by Huntingdon Research Centre, Ltd. 33 p. 

Avian Reproduction 

44024911 Taliaferro, L.; Brewer, L. (1996) The Reproductive Toxicity Test of CGA-215944 Technical 

in Northern Bobwhite, Colinus virginianus: Lab Project Number: 029502: 140-95. 

Unpublished study prepared by Ecotoxicology and Biosystems Associates, Inc. 251 p. 

44411304 Taliaferro, M.; Miller, V. (1997) The Reproductive Toxicity Test of CGA-215944 in the 

Mallard Duck (Anas platyrhynchos): Lab Project Number: 141-95: 029609: EBA-029609. 

Unpublished study prepared by EBA, Inc. 311 p. 

45404301 Wall, S. (2001) Response to EFED Concerning Acceptability of Existing Chronic Mallard 

Reproduction Study (MRID 44411304): Pymetrozine: Lab Project Number: 1170-00. 

Unpublished study prepared by Syngenta Crop Protection, Inc. 9 p. 

46276601 Stafford, J. (2004) CGA-215944 Technical: Reproductive Toxicity Test with the Mallard 

Duck (Anas platyhynchos): Final Report. Project Number: 191/01, 1781/4100. Unpublished 

study prepared by Springborn Smithers Laboratories. 136 p. 

44024912 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through Toxicity of 

CGA-215944 to the Bluegill, Lepomis macrochirus: Lab Project Number: 443-CG: 112-94. 

Unpublished study prepared by T R Wilbury Labs., Inc. 28 p. 

44024913 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through Toxicity of 
44 

CGA-215944 to the Rainbow Trout, Oncorhynchus mykiss: Lab Project Number: 444-CG: 

111-94. Unpublished study prepared by T R Wilbury Labs., Inc. 27 p. 

Acute Toxicity to Freshwater Invertebrates 

44024914 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through 

Toxicity of CGA-215944 to the Daphnia, Daphnia magna: Lab Project Number: 442-

CG: 113-94. Unpublished study prepared by T R Wilbury Labs., Inc. 29 p. 

Acute Toxicity to Estuarine/Marine Organisms 

44024915 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through 

Toxicity of CGA-215944 to the Mysid, Mysidopsis bahia: Lab Project Number: 445-

CG: 115-94. Unpublished study prepared by T R Wilbury Labs., Inc. 28 p. 

44024916 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through 

Toxicity of CGA-215944 to the Sheepshead Minnow, Cyprinodon variegatus: Lab 

Project Number: 446-CG: 114-94. Unpublished study prepared by T R Wilbury 

Labs., Inc. 27 p. 

44024917 Boeri, R.; Kowalski, P.; Ward, T. (1994) CGA-215944: Acute Flow-Through 

Mollusk Shell Deposition Test with CGA-215944: Lab Project Number: 447-CG: 

116-94. Unpublished study prepared by T R Wilbury Labs., Inc. 28 p. 

45208708 Wall, S. (2000) Response to EFED Concerning Acceptability of Existing Acute 

Mysid Shrimp Study: Lab Project Number: 1169-00. Unpublished study prepared by 

Novartis Crop Protection. 11 p. 

Fish Early Life Stage/Aquatic Invertebrate Life Cycle Study 

44024918 Boeri, R.; Kowalski, P.; Ward, T. (1995) CGA-215944: Early Life-Stage Toxicity of 

CGA-215944 to the Rainbow Trout, Oncorhynchus mykiss: Lab Project Number: 

504-CG: 117-94. Unpublished study prepared by T R Wilbury Labs., Inc. 67 p. 

44024919 Boeri, R.; Kowalski, P.; Ward, T. (1995) CGA-215944: Chronic Toxicity of CGA215944 to the Daphnia, Daphnia magna: Lab Project Number: 449-CG: 118-94. 

Unpublished study prepared by T R Wilbury Labs., Inc. 41 p. 

 
45 

Acute oral toxicity in rats 

44024926 Glaza, S. (1991) CGA-215944 Technical: Acute Oral Toxicity Study of CGA215944 Technical in Rats: (Revised) Final Report: Lab Project Number: HWI 

10700623. Unpublished study prepared by Hazleton Wisconsin, Inc. 33 p. 

44024927 Glaza, S. (1995) CGA-215944 Technical: Acute Oral Toxicity Study of CGA215944 50WP-A in Rats: Final Report: Lab Project Number: CHW 50902683. 

Unpublished study prepared by Corning Hazleton Inc. 17 p. 

44411306 Glaza, S. (1997) Acute Oral Toxicity Study of CGA-215944 50WG in Rats: Final 

Report: Lab Project Number: COVANCE 70402016: 70402016: 334-97. 

Unpublished study prepared by Covance Labs., Inc. 19 p. 

44416303 Glaza, S. (1997) Acute Oral Toxicity Study of CGA-215944/CGA-114597 50WPExp in Rats: Final Report: Lab Project Number: COVANCE 70201590. Unpublished 

study prepared by Covance Labs, Inc. 20 p. 

Acute inhalation toxicity in rats 

44024930 Hartmann, P. (1991) CGA-215944 Technical: Acute Inhalation Toxicity in the Rat: 

Lab Project Number: 911186: (Z:\CF-DOC\TOX.0326B2JS). Unpublished study 

prepared by Ciba-Geigy Ltd. 34 p. 

44024931 Bennick, J. (1996) CGA-215944 50WP-A: Acute Inhalation Toxicity Study in Rats: 

Final Report: Lab Project Number: 2670-96. Unpublished study prepared by 

Stillmeadow, Inc. 21 p. 

44411308 Bennick, J. (1997) Acute Inhalation Toxicity Study in Rats: CGA-215944 50WG: 

Final Report: Lab Project Number: 3471-97. Unpublished study prepared by 

Stillmeadow, Inc. 20 p. 

44416305 Bennick, J. (1997) Acute Inhalation Toxicity Study in Rats (CGA-215944/CGA114597 50WP) Final Report: Lab Project Number: 3327-97: SP-FF81-3.C3. 

Unpublished study prepared by Stillmeadow, Inc. 27 p. 

2-generation repro.-rat 

44024950 Fitzgerald, R. (1993) CGA-215944 Technical: Two-Generation Reproduction Study 

in Rats: Final Report: Lab Project Number: 901486: TOX-0228G3LM.1. 

Unpublished study prepared by Ciba-Geigy Ltd. 950 p. Relates to L0000332. 

 
46 

Aquatic plant growth 

44024959 Boeri, R.; Kowalski, P.; Ward, T. (1995) CGA-215944: Toxicity of CGA-215944 to 

the Freshwater Alga, Selenastrum capricornutum: Lab Project Number: 668-CG: 

143-95. Unpublished study prepared by T R Wilbury Labs., Inc. 28 p. 

44024960 Boeri, R.; Kowalski, P.; Ward, T. (1995) CGA-215944: Toxicity of CGA-215944 to 

the Duckweed, Lemna gibba G3: Lab Project Number: 669-CG: 142-95. 

Unpublished study prepared by T R Wilbury Labs., Inc. 28 p. 

Honey bee acute contact 

44024961 Decker, U. (1993) CGA-215944: Laboratory Testing for Oral and Contact Toxicity 

of CGA-215944 Tech to Honey Bees, Apis Melliferal L: Lab Project Number: RCC 

331648: 480-92. Unpublished study prepared by RCC, Research & Consulting Co., 

Ltd. and BRL, Biological Research Laboratories, Ltd. 24 p. 

45579702 Kling, A. (2001) CGA-215944 Tech. (Pymetrozine Tech.): Acute Contact and Oral 

Toxicity on the Honey Bee, Apis mellifera L.: Final Report: Lab Project Number: 

2012504: 2538-01: 20011366/02-BLEU. Unpublished study prepared by 

Arbeitsgemeinschaft, GAB Biotechnologie GmbH & IFU Umweltanalytik GmbH. 52 

p. 

Honey bee residue on foliage 

45579701 Schur, A. (2001) Assessment of Side Effects of CGA-215944 50 WG (A-9364A) on 

the Honey Bee (Apis mellifera L.) in the Field Following Application to Phacelia 

tanacetifolia During Bee-Flight in Spain: Final Report: Lab Project Number: 

2002688: 2540-01: 20011175/S1BFEU. Unpublished study prepared by 

Arbeitsgemeinschaft, GAB Biotechnologie GmbH & IFU Umweltanalytik GmbH. 95 

p. 

45579703 Schur, A. (2001) Assessment of Side Effect of Pymetrozine Tech 50 WG (A-9364 A) 

on the Honey Bee (Apis mellifera L.) in Plum Orchard Following Application During 

Bee Flight: Final Report: Lab Project Number: 2002692: 2545-01: 20011079/S1-

BFEU. Unpublished study prepared by Arbeitsgemeinschaft, GAB Biotechnologie 

GmbH & IFU Umweltanalytik GmbH. 67 p. 
47 

APPENDIX E 

Environmental Fate Bibliography 

161-1 Hydrolysis 

MRID Citation Reference 

44024962 McDonald, J. (1996) CGA-215944: Hydrolysis of (carbon-14)- (Triazine-6) CGA215944 Under Laboratory Conditions at pH 5: Supplemental Report: Lab Project 

Number: ABR-96020: 85-96. Unpublished study prepared by Ciba-Geigy Corp. 

89 p. 

44024963 Kirkpatrick, D. (1995) CGA-215944: The Hydrolysis of CGA-215944 Under 

Laboratory Conditions: Lab Project Number: CBG 570: CBG 570-1: HRC/CBG 

570-1/930675. Unpublished study prepared by Huntingdon Life Sciences Ltd. 

164 p. 

44024964 Kirkpatrick, D. (1995) CGA-215944: (Pyridine-5-(carbon-14))- CGA-215944 

Hydrolysis Under Laboratory Conditions: Lab Project Number: CBG 669: CBG 

669/942733. Unpublished study prepared by Huntingdon Life Sciences Ltd. 127 

p. 

161-2 Photodegradation-water 

MRID Citation Reference 

44411321 Kirkpatrick, D. (1995) (Pyridine-5-(carbon 14)) CGA-215944 the Photolytic 

Degradation in Water: Lab Project Number: CBG 680: 489-94: CBG/942817. 

Unpublished study prepared by Huntingdon Life Sciences Ltd. 136 p. 

44411322 Peters, J. (1997) Photodegradation of (carbon 14)-Triazine-6-CGA-215944 in 

pH Buffered Solution Under Artificial Light: Lab Project Number: ABR-97038: 

262-97. Unpublished study prepared by Novartis Crop Protection, Inc. 127 p. 

44411323 Parker, S. (1988) Development of a method to investigate the 

photodegradation of pesticides. Brighton Crop Protection Conference-Pest and 

Diseases p. 663-668. 

44471702 Shaw, D. (1997) CGA-215944 (Triazine-6-(Carbon 14)) Rate of Photolytic 

Degradation in Water: Lab Project Number: CBG 811: 457-96: CBG 

811/962086. Unpublished study prepared by Huntingdon Life Sciences Ltd. 

118 p. 
48 

161-3 Photodegradation-soil 

MRID Citation Reference 

44411323 Parker, S. (1988) Development of a method to investigate the 

photodegradation of pesticides. Brighton Crop Protection Conference-Pest 

and Diseases p. 663-668. 

44411324 Schulze-Aurich, J. (1995) Photolysis (5-(carbon 14))--Pyridine-Labelled CGA215944 on Soil Surface Under Laboratory Conditions: Lab Project Number: 

94SA02: 488-94: PR 94SA02. Unpublished study prepared by Ciba-Geigy Ltd. 

195 p. 

44411325 Schulze-Aurich, J. (1995) Photolysis (5-(carbon 14))--Triazine-Labelled CGA215944 on Soil Surface Under Laboratory Conditions: Lab Project Number: 

93MU02: 606-93: PR 50/94. Unpublished study prepared by Ciba-Geigy Ltd. 

176 p. 

45208701 Sparrow, K. (2000) Photodegradation of (carbon 14)-Pyridinyl-2-CGA-215944 

on Soil Surface Under Artificial Light: Lab Project Number: 543-00. 

Unpublished study prepared by Novartis Crop Protection, Inc. 134 p. 

45208702 Sparrow, K. (2000) Photodegradation of (carbon 14)-Triazinyl-2-CGA-215944 

on Soil Surface Under Artificial Light: Lab Project Number: 544-00. 

Unpublished study prepared by Novartis Crop Protection, Inc. 128 p. 

162-1 Aerobic soil metabolism 

MRID Citation Reference 

44024965 Das, Y. (1996) CGA-215944: Metabolism of (Pyridinyl-5- (carbon-14)) CGA215944 Under Aerobic Soil Conditions: Lab Project Number: 94011: 45-94. 

Unpublished study prepared by Innovative Scientific Services, Inc. 479 p. 

44024966 Das, Y. (1996) CGA-215944: Metabolism of (Triazinyl-6- (carbon-14)) CGA215944 Under Aerobic Soil Conditions: Lab Project Number: 94013: 47-94. 

Unpublished study prepared by Innovative Scientific Services, Inc. 487 p. 

44024986 Phelps, W. (1996) CGA-215944: Ecochemistry of CGA-215944: Lab Project 

Number: ABR-96030. Unpublished study prepared by Ciba-Geigy Corp. 54 

p. 

162-3 Anaerobic aquatic metab. 

MRID Citation Reference 

44024967 Das, Y. (1996) CGA-215944: Metabolism of (Pyridinyl-5- (carbon-14)) CGA215944 Under Anaerobic Aquatic Soil Conditions: Lab Project Number: 

94012: 46-94. Unpublished study prepared by Innovative Scientific 

Services, Inc. 513 p. 

44024968 Das, Y. (1996) CGA-215944: Metabolism of (Triazinyl-6- (carbon-14)) CGA-
49 

215944 Under Anaerobic Aquatic Soil Conditions: Lab Project Number: 

94014: 48-94. Unpublished study prepared by Innovative Scientific 

Services, Inc. 606 p. 

44024986 Phelps, W. (1996) CGA-215944: Ecochemistry of CGA-215944: Lab Project 

Number: ABR-96030. Unpublished study prepared by Ciba-Geigy Corp. 54 

p. 

163-1 Leach/adsorp/desorption 

MRID Citation Reference 

44024969 Gohdes, M. (1996) CGA-215944: The Adsorption and Desorption of 

(carbon-14) CGA-215944 on Representative Agricultural Soils: Lab Project 

Number: CHW 6117-293: 501-95. Unpublished study prepared by Corning 

Hazleton Inc. 99 p. 

44024970 Gohdes, M. (1996) CGA-215944: Column Leaching Characteristics of 

(carbon-14)-CGA-215944 in Four Soil Types: Lab Project Number: CHW 

6117-297: 55-95. Unpublished study prepared by Corning Hazleton Inc. 146 

p. 

44024971 Gohdes, M. (1996) CGA-215944: Column Leaching Characteristics of Aged 

(carbon-14)-Triazine-CGA-215944 in Four Soil Types: Lab Project Number: 

CHW 6117-299: 56-95. Unpublished study prepared by Corning Hazleton 

Inc. 355 p. 

44024972 Gohdes, M. (1996) CGA-215944: Column Leaching Characteristics of Aged 

(carbon-14)-Pyridine-CGA-215944 in Four Soil Types: Lab Project Number: 

CHW 6117-317: 57-95. Unpublished study prepared by Corning Hazleton 

Inc. 359 p. 

44024986 Phelps, W. (1996) CGA-215944: Ecochemistry of CGA-215944: Lab Project 

Number: ABR-96030. Unpublished study prepared by Ciba-Geigy Corp. 54 

p. 

44411326 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-CGA359009 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-349: 6117-349: 224-96. Unpublished study prepared by 

Covance Labs., Inc. 103 p. 

44411327 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-CGA180777 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-343: 6117-343: 227-96. Unpublished study prepared by 

Covance Labs., Inc. 110 p. 

44411328 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-CGA300407 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-345: 6117-345: 226-96. Unpublished study prepared by 

Covance Labs., Inc. 83 p. 

44411329 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-GS23199 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-365: 6117-365: 48-97. Unpublished study prepared by 

Covance Labs., Inc. 82 p. 
50 

44411330 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-CGA249257 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-347: 6117-347: 225-96. Unpublished study prepared by 

Covance Labs., Inc. 87 p. 

44411331 Gohdes, M. (1997) The Adsorption and Desorption of (carbon 14)-CGA215525 on Representative Agricultural Soils: Lab Project Number: 

COVANCE 6117-295: 223-96: NOVARTIS 223-96. Unpublished study 

prepared by Covance Labs., Inc. 137 p. 

45208703 Sparrow, K. (2000) Soil Adsorption and Desorption of (Triazinyl-6(carbon 

14)-CGA-215525-OH by the Batch Equilibrium Method: Lab Project 

Number: 63-99. Unpublished study prepared by Novartis Crop Protection, 

Inc. 79 p. 

164-1 Terrestrial field dissipation 

MRID Citation Reference 

44024973 Sandmeier, P. (1993) Outdoor Confined Accumulation Study on Rotational 

Crops and Field Dissipation after Bareground Soil Application of (Triazine-6-

(carbon-14)) CGA-215944: Lab Project Number: 20/93: MR 20/93. 

Unpublished study prepared by Ciba-Geigy Ltd. 61 p. 

44411332 Kabler, A. (1997) Independent Laboratory Validation of Novartis Method AG660: Analytical Method for the Determination of CGA-180777, A Metabolite of 

CGA-215944, in Soil by High Performance Liquid Chromatography with UV 

and MS Detection Including Validation Data: Final Report: Lab Project 

Number: 305-97: ABR-97045: AG-660. Unpublished study prepared by 

Novartis Crop Protection, Inc. 131 p. 

44411333 Vargo, J. (1995) Analytical Method for the Determination of CGA-215944 and 

its Metabolites CGA-249257 and 2U in Soil by High Performance Liquid 

Chromatography with Mass Spectrometric Detection Including Validation 

Data: Lab Project Number: AG-641: 334-95: 344001. Unpublished study 

prepared by Novartis Crop Protection, Inc. 77 p. 

44411334 Speth, R. (1997) Terrestrial Field Dissipation of CGA-215944 50WP on Bare 

Soil in New York: Final Report: Lab Project Number: 189-95: 42962: 344001. 

Unpublished study prepared by Ciba Crop Protection. 481 p. 

44411335 Vargo, J. (1997) Analytical Method for the Determination of GS-23199 and 

CGA-294849, Metabolites of CGA-215944, in Soil by High Performance 

Liquid Chromatography with UV Detection Including Validation Data: Lab 

Project Number: AG-666: 376-96: 344001. Unpublished study prepared by 

Novartis Crop Protection, Inc. 84 p. 

44411336 Kabler, A. (1997) Independent Laboratory Validation of Novartis Method AG660: Analytical Method for the Determination of CGA-180777, a Metabolite of 

CGA-215944, in Soil by High Performance Liquid Chromatography with UV 

and MS Detection Including Validation Data: Amendment to the Final Report: 

Lab Project Number: 305-97. Unpublished study prepared by Novartis Crop 

Protection, Inc. 5 p. 

44411337 Gresham, M. (1997) Independent Laboratory Validation of Ciba Analytical 
51 

Method No. AG-641, Analytical Method for the Determination of CGA-215944 

and its Metabolites CGA-249257 and 2U in Soil by High Performance Liquid 

Chromatography with Mass Spectrometric Detection: Final Report: Lab 

Project Number: 630-95: 42961: AG-641. Unpublished study prepared by 

ABC Labs., Inc. 166 p. 

44411338 Jones, G.; Fieser, J.; Speth, R. (1997) Terrestrial Field Dissipation of CGA215944 50WP on Crop (Tomatoes) and Bare Soil in California: Final Report: 

Lab Project Number: 190-95: 42686: 95512. Unpublished study prepared by 

ABC Labs., Inc. 539 p. 

44411339 Vargo, J. (1996) Analytical Method for the Determination of CGA-180777, a 

Metabolite of CGA-215944, in Soil by High Performance Liquid 

Chromatography with UV and MS Detection Including Validation Data: Lab 

Project Number: AG-660: 285-96: 344001. Unpublished study prepared by 

Novartis Crop Protection, Inc. 74 p. 

44411340 Coody, P.; Lightle, S. (1997) Soil Dissipation of (carbon 14)CGA-215944 

Under Actual Field Conditions in Georgia: Interim Report: Lab Project 

Number: 1052: 279-96. Unpublished study prepared by PTRL East, Inc. and 

Hickey's Agri-Services Lab. 269 p. 

44411341 Lightle, S.; Coody, P. (1997) Soil Dissipation of (carbon 14)CGA-215944 

Under Actual Field Conditions in California: Interim Report: Lab Project 

Number: 1053: 280-96: 1973. Unpublished study prepared by PTRL East, 

Inc. and ABC Labs., California. 285 p. 

44471703 Leppert, B.; Manuli, P. (1997) Terrestrial Field Dissipation Study for CGA215944 in Georgia: Lab Project Number: 191-95: SARS-95-GA-85: 191-95 

PART A. Unpublished study prepared by Stewart Agricultural Research 

Services, Inc., Hickey's Agri-Services Laboratory and Novartis Crop 

Protection, Inc. 635 p. 

44647901 Fieser, J.; Speth, R. (1998) Terrestrial Field Dissipation of CGA-215944 

50WP on Bare Soil in New York: Final Report Addendum No.1: Lab Project 

Number: 189-95: 42962: AG-660. Unpublished study prepared by ABC 

Laboratories, Inc. 168 p. 

44647903 Fieser, J.; Speth, R. (1998) Terrestrial Field Dissipation of CGA-215944 

50WP on Crop (Tomatoes) and Bare Soil in California: Final Report 

Addendum No. 1: Lab Project Number: 190-95: 42686: AG-666. Unpublished 

study prepared by ABC Laboratories, Inc. 181 p. 

44647904 Wickremesinhe, E.; Manuli, P. (1998) Terrestrial Field Dissipation of CGA215944 in Georgia: Final Report Addendum: Lab Project Number: 191-95: 

003-26: AG-666. Unpublished study prepared by Centre Analytical 

Laboratories, Inc. 217 p. 

45208704 Lightle, S.; Coody, P.; Atkins, R. (1999) Soil Dissipation of (carbon 14)CGA215944 Under Actual Field Conditions in Georgia: Lab Project Number: 1052: 

279-96. Unpublished study prepared by PTRL East, Inc., Hickey's AgriServices Laboratory, and Agvise Laboratories, Inc. 571 p. 

45208705 Lightle, S.; Coody, P.; Atkins, R. (2000) Soil Dissipation of (carbon 14)CGA215944 Under Actual Field Conditions in California: Final Report: Lab Project 

Number: 1053: 280-96. Unpublished study prepared by PTRL East, Inc., 

PTRL West, Inc. and Agvise Laboratories, Inc. 561 p. 

45208706 Lightle, S.; Marsh, J.; Atkins, R. (2000) Frozen Storage Stability of (carbon 
52 

14)CGA-215944 in Soil from Georgia: Final Report: Lab Project Number: 

1060:321-96. Unpublished study prepared by PTRL East, Inc. 113 p. 

45208707 Marsh, J.; Atkins, R. (2000) Frozen Storage Stability of (carbon 14)CGA215944 in Soil from California: Final Report: Lab Project Number: 1061: 394-

96. Unpublished study prepared by PTRL East, Inc. 121 p. 

45387801 Speth, R.; Gresham, M. (2000) Terrestrial Field Dissipation of CGA-215944 

50WP on Bare Soil in New York Addendum No. 2 to Final Report (MRID 

44411334): Lab Project Number: 42962: 189-95. Unpublished study 

prepared by Novartis Crop Protection, Inc. & ABC Labs., Inc. 44 p. 

45387802 Speth, R.; Gresham, M. (2000) Terrestrial Field Dissipation of CGA-215944 

50WP on Crop (Tomatoes) and Bare Soil in California Addendum No. 2 to 

Final Report (MRID 44411334): Lab Project Number: 190-95: 42686. 

Unpublished study prepared by Novartis Crop Protection, Inc. & ABC Labs., 

Inc. 44 p. 

45387803 Manuli, P.; Wickremesinhe, E. (2000) Terrestrial Field Dissipation Study for 

CGA-215944 in Georgia Addendum No. 2 to Final Report (EPA MRID 

44471703): Lab Project Number: 003-026: 191-95. Unpublished study 

prepared by Centre Analytical Labs., Inc. 27 p. 

165-1 Confined rotational crop 

MRID Citation Reference 

44024973 Sandmeier, P. (1993) Outdoor Confined Accumulation Study on Rotational 

Crops and Field Dissipation after Bareground Soil Application of (Triazine-6-

(carbon-14)) CGA-215944: Lab Project Number: 20/93: MR 20/93. 

Unpublished study prepared by Ciba-Geigy Ltd. 61 p. 

44024974 Gross, D. (1995) Outdoor Confined Accumulation Study on Rotational Crops 

after Bareground Soil Application of (Pyridine-5-(carbon-14)) CGA-215944: 

Lab Project Number: 19/94: PMR 19/94: 92DG44. Unpublished study 

prepared by Ciba-Geigy Ltd. 52 p. 

44572209 Fleischmann, T. (1998) Study on Confined Rotational Crops after Soil 

Application of Triazine-14C-CGA-215944 and Pyridine-14C-CGA-215944: 

Lab Project Number: ABR-97018: 457-95: BIOL-97009. Unpublished study 

prepared by Novartis Crop Protection, Inc. 276 p. {860.1850} 

165-2 Field rotational crop 

MRID Citation Reference 

44716601 Joseph, T. (1998) CGA-215944--Field Accumulation in Rotational Crops: 

Final Report: Lab Project Number: 31-97: 07-IR-008-97: 02-IR-037-97. 

Unpublished study prepared by Novartis Residue Chemistry and A&L 

Great Lakes Laboratories, Inc. 193 p. {OPPTS 860.1900}. 
53 

875.1000 Background for application exposure monitoring test 

guidelines 

MRID Citation Reference 

46470503 Peranginangin, N. (2005) Pymetrozine (CGA-215944): Standard Index 

Reservoir Scenario of Potato for Pymetrozine: A PRZM/EXAMS 

Modeling Study for Surface Water Exposure Assessment. Project 

Number: T0A3264/01. Unpublished study prepared by Syngenta Crop 

Protection, Inc. 35 p. 

Non-Guideline Studies 

46470502 Perine, J.; Peranginangin, N. (2005) Pymetrozine (CGA-215944): 

Preliminary Drinking Water Exposure Assessment for Pymetrozine on 

Potatoes. Project Number: T002878/05. Unpublished study prepared 

by Syngenta Crop Protection, Inc. 9 p. 

44647902 Petit, J. B. 1998. Independent laboratory validation of analytical 

method AG-666: "Analytical method for the determination of GS-23 

199 and CGA-294849, metabolites of CGA-215944, in 

soil by high performance liquid chromatography with UV detection 

including validation data." Novartis Laboratory Project ID: 324-97 and 

CAL Laboratory Project ID: 003-29. Unpublished study performed by 

Centre Analytical Laboratories Inc. (CAL), State College, PA; and 

submitted by Novartis Crop Protection, Inc., Greensboro, NC. 

44024986 Phelps, W. (1996) CGA-215944: Ecochemistry of CGA-215944: Lab 

Project Number: ABR-96030. Unpublished study prepared by CibaGeigy Corp. 54 p. 

 
54 

APPENDIX F 

ECOSAR Results 

ECOSAR Version 1.10 Results Page 

Pymetrozine 

SMILES : O=C2N(N=Cc1cccnc1)CC(=NN2)C

 MOL FOR: C10 H11 N5 O1 

MOL WT : 217.23 

Log Kow: 0.891 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: -0.18 (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: 217.00 (deg C, PhysProp DB exp value for Wat Sol est) 

Wat Sol: 9.936E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: 290 (mg/L, PhysProp DB exp value) 

 

Values used to Generate ECOSAR Profile-------------------------------------- 

Log Kow: 0.891 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 290 (mg/L, PhysProp DB exp value) 

 

Available Measured Data from ECOSAR Training Set 

 No Data Available 

ECOSAR v1.1 Class-specific Estimations 

Hydrazines 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Hydrazines : Fish 96-hr LC50 5.211 

Hydrazines : Daphnid 48-hr LC50 30.837 

Hydrazines : Green Algae 96-hr EC50 1.250 

Hydrazines : Fish ChV 0.400 ! 

Hydrazines : Daphnid ChV 2.596 ! 

Hydrazines : Green Algae ChV 0.332 

=========================== ================== ======== ====== 

Neutral Organic SAR : Fish 96-hr LC50 1766.678 * 

(Baseline Toxicity) : Daphnid 48-hr LC50 757.371 * 

 : Green Algae 96-hr EC50 697.971 * 

 : Fish ChV 153.045 

 : Daphnid ChV 66.418 

 : Green Algae ChV 92.108 
55 

Degradate (CGA-359009) 

ECOSAR Version 1.10 Results Page 

 SMILES : O=C1(N(N=C(C(N1N=Cc2cnccc2)O)C)) 

 

MOL FOR: C10 H11 N5 O2 

MOL WT : 233.23 

Log Kow: -0.647 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) 

Wat Sol: 1.019E+005 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: (PhysProp DB exp value) 

 Values used to Generate ECOSAR Profile 

-------------------------------------- 

Log Kow: -0.647 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 1.019E+005 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

 

Available Measured Data from ECOSAR Training Set 

------------------------------------------------ 

 No Data Available 

-------------------------------------- 

ECOSAR v1.1 Class-specific Estimations 

Hydrazines 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Hydrazines : Fish 96-hr LC50 19.921 

Hydrazines : Daphnid 48-hr LC50 171.582 

Hydrazines : Green Algae 96-hr EC50 4.107 

Hydrazines : Fish ChV 2.414 ! 

Hydrazines : Daphnid ChV 19.439 ! 

Hydrazines : Green Algae ChV 0.893 

=========================== ================== ======== ====== 

Neutral Organic SAR : Fish 96-hr LC50 45663.352 

(Baseline Toxicity) : Daphnid 48-hr LC50 14620.531 

 : Green Algae 96-hr EC50 13355.061 

 : Fish ChV 3345.564 

 : Daphnid ChV 1003.074 

 : Green Algae ChV 836.764 
56 

ECOSAR Version 1.10 Results Page 

 CGA 215525 

SMILES : O=C1(NN=C(CN1N)C) 

CHEM : 

CAS Num: 

ChemID1: 

MOL FOR: C4 H8 N4 O1 

MOL WT : 128.13 

Log Kow: -1.453 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) 

Wat Sol: 7.978E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: (PhysProp DB exp value) 

 -------------------------------------- 

Values used to Generate ECOSAR Profile 

-------------------------------------- 

Log Kow: -1.453 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 7.978E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Available Measured Data from ECOSAR Training Set 

 No Data Available 

-------------------------------------- 

ECOSAR v1.1 Class-specific Estimations 

Hydrazines 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Hydrazines : Fish 96-hr LC50 21.293 

Hydrazines : Daphnid 48-hr LC50 223.29 

Hydrazines : Green Algae 96-hr EC50 4.055 

Hydrazines : Fish ChV 3.279 ! 

Hydrazines : Daphnid ChV 29.557 ! 

Hydrazines : Green Algae ChV 0.795 

=========================== ================== ======== ====== 

Neutral Organic SAR : Fish 96-hr LC50 1.33e+005 * 

(Baseline Toxicity) : Daphnid 48-hr LC50 36520.914 

 : Green Algae 96-hr EC50 33205.391 

 : Fish ChV 8919.673 

 : Daphnid ChV 2203.103 
57 

 : Green Algae ChV 1407.994ECOSAR Version 1.10 

Results PageCGA 300407 

SMILES : c1cc(cnc1)C=O

CHEM : 

CAS Num: 

ChemID1: 

MOL FOR: C6 H5 N1 O1 

MOL WT : 107.11 

Log Kow: 0.522 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: 0.29 (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) 

Wat Sol: 6.286E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: (PhysProp DB exp value) 

Values used to Generate ECOSAR Profile 

-------------------------------------- 

Log Kow: 0.522 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 6.286E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

 Available Measured Data from ECOSAR Training Set 

 Measured 

CAS No Organism Duration End Pt mg/L (ppm) Ecosar Class Reference 

=========== ========== ========== ====== ========== 

=========================== ========================= 

000500-22-1 Fish 96-hr LC50 16.4 Aldehydes (Mono) DUL 

-------------------------------------- 

ECOSAR v1.1 Class-specific Estimations 

-------------------------------------- 

Aldehydes (Mono) 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Aldehydes (Mono) : Fish 96-hr LC50 36.381 

Aldehydes (Mono) : Daphnid 48-hr LC50 122.696 

Aldehydes (Mono) : Green Algae 96-hr EC50 133.972 

Aldehydes (Mono) : Fish ChV 9.856 

Aldehydes (Mono) : Daphnid ChV 13.540 ! 

Aldehydes (Mono) : Green Algae ChV 35.013 

Aldehydes (Mono) : Fish (SW) 96-hr LC50 51.866 

Aldehydes (Mono) : Fish (SW) ChV 4.927 ! 

Neutral Organic SAR : Fish 96-hr LC50 1871.123 
58 

(Baseline Toxicity) : Daphnid 48-hr LC50 747.808 

 : Green Algae 96-hr EC50 687.693 

 : Fish ChV 155.696 

 : Daphnid ChV 61.822 

 : Green Algae ChV 75.877 

ECOSAR Version 1.10 Results Page 

CGA 249257 

 C1(NCC(=NN1)C)=O 

 

SMILES : O=C1(NCC(=NN1)C) 

CHEM : 

CAS Num: 

ChemID1: 

MOL FOR: C4 H7 N3 O1 

MOL WT : 113.12 

Log Kow: 0.292 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: (deg C, PhysProp DB exp value for Wat Sol estimate) 

Wat Sol: 2931 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: (PhysProp DB exp value) 

 Values used to Generate ECOSAR Profile 

-------------------------------------- 

Log Kow: 0.292 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 2931 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Available Measured Data from ECOSAR Training Set 

 No Data Available 

ECOSAR v1.1 Class-specific Estimations 

-------------------------------------- 

Hydrazines 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Hydrazines : Fish 96-hr LC50 4.452 

Hydrazines : Daphnid 48-hr LC50 30.499 

Hydrazines : Green Algae 96-hr EC50 1.007 

Hydrazines : Fish ChV 0.408 ! 

Hydrazines : Daphnid ChV 2.883 ! 

Hydrazines : Green Algae ChV 0.247 
59 

=========================== ================== ======== ====== 

========== 

Neutral Organic SAR : Fish 96-hr LC50 3180.190 * 

(Baseline Toxicity) : Daphnid 48-hr LC50 1216.693 

 : Green Algae 96-hr EC50 1117.403 

 : Fish ChV 258.075 

 : Daphnid ChV 96.959 

 : Green Algae ChV 110.289 

ECOSAR Version 1.10 Results Page 

 CGA-23199 

SMILES : O=C1(NC(=O)(C(=NN1)C)) 

MOL FOR: C4 H5 N3 O2 

MOL WT : 127.10 

Log Kow: -0.116 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: 211.00 (deg C, PhysProp DB exp value for Wat Sol est) 

Wat Sol: 6279 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: (PhysProp DB exp value) 

 

Values used to Generate ECOSAR Profile 

Log Kow: -0.116 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 6279 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Available Measured Data from ECOSAR Training Set 

 No Data Available 

ECOSAR v1.1 Class-specific Estimations 

Hydrazines 

Carbonyl Ureas 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

Hydrazines : Fish 96-hr LC50 7.002 

Hydrazines : Daphnid 48-hr LC50 52.978 

Hydrazines : Green Algae 96-hr EC50 1.521 

Hydrazines : Fish ChV 0.725 ! 

Hydrazines : Daphnid ChV 5.417 ! 

Hydrazines : Green Algae ChV 0.354 

Carbonyl Ureas : Fish 96-hr LC50 235.604 

Carbonyl Ureas : Daphnid 48-hr LC50 567.725 
60 

Carbonyl Ureas : Green Algae 96-hr EC50 0.010 

Carbonyl Ureas : Fish ChV 1.699 

Carbonyl Ureas : Daphnid ChV 7.066 

Carbonyl Ureas : Green Algae ChV 0.003 

Carbonyl Ureas : Fish (SW) 96-hr LC50 205.812 

Carbonyl Ureas : Mysid (SW) 96-hr LC50 3657.087 

Carbonyl Ureas : Fish (SW) ChV 4.694 

=========================== ================== ======== ====== 

========== 

Neutral Organic SAR : Fish 96-hr LC50 8295.968 * 

(Baseline Toxicity) : Daphnid 48-hr LC50 2937.875 

 : Green Algae 96-hr EC50 2691.808 

 : Fish ChV 644.013 

 : Daphnid ChV 219.389 

 : Green Algae ChV 218.128 

ECOSAR Version 1.10 Results Page 

 CGA 180777 

SMILES : c1cc(cnc1)C(=O)(O) 

CHEM : 

CAS Num: ChemID1: 

MOL FOR: C6 H5 N1 O2 

MOL WT : 123.11 

Log Kow: 0.686 (EPISuite Kowwin v1.68 Estimate) 

Log Kow: (User Entered) 

Log Kow: 0.36 (PhysProp DB exp value - for comparison only) 

Melt Pt: (User Entered for Wat Sol estimate) 

Melt Pt: 236.60 (deg C, PhysProp DB exp value for Wat Sol est) 

Wat Sol: 1.006E+004 (mg/L, EPISuite WSKowwin v1.43 Estimate) 

Wat Sol: (User Entered) 

Wat Sol: 1.8E+004 (mg/L, PhysProp DB exp value) 

 Values used to Generate ECOSAR Profile 

Log Kow: 0.686 (EPISuite Kowwin v1.68 Estimate) 

Wat Sol: 1.8E+004 (mg/L, PhysProp DB exp value) 

 

Available Measured Data from ECOSAR Training Set 

 No Data Available 

ECOSAR v1.1 Class-specific Estimations 
61 

-------------------------------------- 

Neutral Organics-acid 

 Predicted 

ECOSAR Class Organism Duration End Pt mg/L (ppm) 

=========================== ================== ======== ====== 

========== 

--> Acid moeity found: Predicted values multiplied by 10 

Neutral Organics-acid : Fish 96-hr LC50 15314.189 

Neutral Organics-acid : Fish 14-day LC50 15006.738 

Neutral Organics-acid : Daphnid 48-hr LC50 7713.472 

Neutral Organics-acid : Green Algae 96-hr EC50 5812.017 

Neutral Organics-acid : Fish ChV 1297.290 

Neutral Organics-acid : Daphnid ChV 535.852 

Neutral Organics-acid : Green Algae ChV 694.339 

Neutral Organics-acid : Fish (SW) 96-hr LC50 19128.344 * 

Neutral Organics-acid : Mysid 96-hr LC50 34624.660 * 

Neutral Organics-acid : Fish (SW) ChV 930.632 

Neutral Organics-acid : Mysid (SW) ChV 4417.842 

Neutral Organics-acid : Earthworm 14-dayLC50 2929.361 

Note: * = asterisk designates: 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. 

 

 NOTE: ! = exclamation designates: The toxicity value was estimated through 

 application of acute-to-chronic ratios per methods outlined in 

 the ECOSAR Methodology Document provided in the ECOSAR Help Menu.