UNITED STATES ENVIRONMENTAL PROTECTlON AGENCY WASHINGTON D.C., 20460



### Date: Chemical: 

### PC Code: Barcode: OFFICE OF CHEMICAL SAFETY AND POLLFTION PREVENTION 

### November 25, 2013 Fl azasulfuron 119011 DP 408779 

### MEMORANDUM SUBJECT: Re view of Batch Equilibrium Study on Flazasulfuron and Degradates on Two Alkaline Soils FROM : Andrew Shelby, Physical Scientist;-

- ....._....-......- - //?,,,.

- -----

### -~ii-**z.S--I~** Mark Corb in, Branch Chief _ .

### ~G_A Environmental Risk Branch 6 \ 

### \.1') .. \') Environmental Fa te a nd Effects Division (7507P TO : K.hue Nguyen, Risk Manager Reviewer Pesticide Re-Evaluation Division (7508P) The Environmental Fate and Effects Divis ion (EFED) has completed its review of a study [MRIDs: 49030002 ] submitted on environmental fate of flazasulfuron. The study is classified as acceptable . fi ndings of the review are presented in the following table.
Enviror• irnental fate data**classificat~ons** for etbaboxam MRID Study Classification 1 Remarks 

### 49030002 Acceptable 10PPI N Classifications : Acceptable/Guideline; Acceptable/Non-Guideline; Cited; Confirmatory; Decision Deferred; Extraneous submission; In Review; No Decision; Partially Acceptable; Supplemental : Unacceptable/Guideline; Unacceptable/Non

- Guideline; Upgradeable .

I

### Test Material: Flazasulfuron 

### MRID 49030002 

### Title: Shepler, K. 2012. Adsorption/desorption of [ 14 C) flazasulfuron , DTPU , DTPP , ADMP , and T PSA on one soil and a sediment. 

### EPA PC Code: 119011 

### OCSP P Guideline: 835.1230 

### For C DM Smith
Primar y Reviewer: Kindra Bozicevich 

### Signature: Date: 1 1/ 19 / 13



### Second ary Reviewer: Joan Harlin 

### Signature: Date: 11/19 / 13 

### QC/QA Manager: Joan Gaidos 

### Signature: Date: 11 / 19 / 1 3Flazasulfuron (PC 119011) MRID 49030002 

### Adsorption and desorption of Flazasulfuron, DTPU, DTPP, ADMP, and TPSA on 

### one soil and a sediment. Report:

Document No. : 

### Guideline: Statements:

Classification:

PC Code : Reviewer: MRID 49030002. Shepler, K. 2012. Adsorption/desorption of [ 14C]flazasulfuron, DTPU, DTPP, ADMP, and TPSA on one soi l and a sediment. Unpub lished study performed by PTRL West, Hercul e s, California; sponsored and submitted by Ishihara Sangyo Kaisha, Ltd., Osaka, Japan. Report Number 2293 W-1. Project Number 2293 W. Experimental initiation June 21, 2012 and completion September 6, 2012 (p. 13). Study completion date December 26, 2012. MRID 49030002 OCSPP 835.1230 The st udy was conducted in accordance with USEPA 40 CFR Part 160 (p. 3). Signed and dated Data Confidentiality, GLP, and Quality As surance statements were provided (pp. 2-4). A Certification of Authentic ity was not provided. This study i s acceptable. The study was conducted using the par e nt compound flazasufuron as well as four transformation products. The study was conducted using only two types of soils. The parent compound was found to be highly unstable in so lution with significant degradation. 119011 Andrew Shelby EPA 

### Signature·//

# .A-..~-A**· ~**  Date :

### 11/~} . -...- ... --

### ~ Executive Summary In a batch equilibrium study, two U.S . soils (p H range 8.2-8.5) were used to measure sorption coefficients of [ 1 4C]- labe led flazasulfuron and its soil metabolites DTPU , DTPP , ADMP, and TPSA in darkness at 25°C. For the parent compound flazasulfuron, determined Freundlich Adsorption Coefficient (KF) values ranged from 0.16 to 0. 23 L/kg (mean KF 

## =0.19 L/kg); re spective Krnc values ranged from 20 to 77 L/kg (mean 

### KFoc 

## = 48 .2 L/kg). 1 Freundlich Desorption Coefficients (KF -des; range 0.89 to 0.93 L/kg, m ean KF 

## =0.91 L/kg) were higher than those obtained for the initial sorption measurement , indicating a degree of irreversible sorption. Percent adsorption and percent desorpt ion, as percent of the adsorbed, were not determined. Freundlich exponents corresponding to KF values ranged from 0.78 to 0.88 across all test soils.

1 Sorption is a generic term that applies to absorption, adsorption, and desorption processes. Adsorption refers to sorption onto a two-dimensional surface; absorption refers to sorption into a three dimensional matrix. Both types of sorption occur in soils and sediments. Desorption refers to a sorbate becoming desorbed from a sorbent. Desorption distribution coefficients are measured by removing solution from a sorpt ion experiment and add in g fresh solution, so that all material measured in solution will be the desorbed material. The guide line uses the term adsorption in place of sorption and refers to the ini t ial measurement of sorption. 2 of29

### '

.... 

## - 

## . " Flazasulfuron (PC I 19011) 

### MRJD 49030002 

### Table 3 summarizes the adsorption coefficients measured in the study. Table 4 summa rizes the desorption coefficients measured in the study. Mass balances ranged from 96.2

- 1 11 .6% of the app li ed fo r the soils treated with [ 14

### C]fl azasulfuron and 87 . 5- 104.0% for soils treated with [ 14

### C]-labe led TPSA, DTPU, DTPP, and ADMP. HPLC analysis of test soils treated at the highest test concentration (5 mg/L) showed that [ 14 

### C]flazasulfuron was unstable in 

### both test soils. TPSA, DTPU, D T PP, and ADMP were stable in 

### both test soils. Coeffi c ients of variation (CV) ranged from 0.02 to 1.1and0.2 to 0.8 , respectively, across al l [ 14

### C]-treated soils for adsorption KF 

### and KFoc, 

### and 0.03 to 0.7 and 0. 1 to 0 . 6, respecti vely, across all [ 14

### C]-treated soils for desorpti on KF 

### and K Foc · 

### Results Synopsis :

3 of29Flazasulfuron (PC 1190 11) MRlD 49030002



### T bl 1 S

a e 

# . ummary of Ad f /D 

### sorp aou f 

### R It A 

### esorp aou esu s Soil/ Regressed Kd Regressed KF 1/n for KFoc Sediment, (L/kg-soil) Range of Koc( L/kg- ((L/kg

- soi1>· 1'") adsorption**(L/k~-oc>·** Ceq %0C Kd(L/kg- OC) I") Range pH Value ± p-value soil) Value ± 

# I Value ± Value± (mg/L) SE 

### ,.2 Value ± SE SE**r~** p-value SE SE Flazasulfuron

Adsorption Golden Lake Sand 0.20 ± 0.0 0.985 l.5£-09 0 . 17-0.39 67 ± 3 0.23 ± 1.0 0.996 6 .2 ±E-11 0.88 ± 0.0 77 ± 344 0.0354- (0.3% 

## oc 3.8065 pH 8.5) WY C lay 0.0379- (0.8%0C, 0.10 ± 0.0 0.834 8.7E-05 0.07-0.28 12 ± 2 0.16 ± l.I 0.962 4.4E-08 0.78 ± 0.l 20 ± 137 4. 1293 pH 8.3) Desorption Golden Lake San d 0.92 ± 0.1 0.944 6.3E-07 0.71-1.52 308 ± 25 0.89 ± 1.1 0.987 0.364 0.89 ± 0 .0 298 ± 375 0.0042- (0.3%0C 0.3564 pH 8.5) WY Clay 0.0028- (0.8%0C, 1.17 ± 0.2 0.775 0.0004 0.64-3.14 146 ± 26 0.93 ± l. 4 0.901 0.834 0.77 ± 0 . I 116 ± 176 0 . 1805 pH 8.3)

4 of29F l azasulfuron (P C 119011) MRID 49030002



### Table 1 (coot). Summary of Adsorption/Desorption ResultsA So il/ R egress ed Kd Regressed K F l / n for Kroc 

# I Sediment , (L / kg-soil) Range of Koc ( U kg- ((Ukg

- soi1 > · 110) adsorption**(L k~-oc** **>-** Ceq %0C K.i(Ukg- OC) I") Range pH Value ± p-value soil) Value± 

# I Va lue ± Va lue ± (mg/L) 

### SE rz Value ± SE 

### SE rz p-value 

### SE SE TPSA Adsorption Gold en Lake Sand 0 . 10 ± 0.0 0.995 7.5E-12 0.09

-0. 12 3 5 ± 0.8 0 . 11 ± 1.0 0.998 2.0E- 1 3 0 .97 ± 0.0 35 ± 3 42 0.0382- (0.3%0 C 4.5430 pH 8.5) WY C l ay 0 .0380- (0.8%0 C , 0.10 ± 0.0 0.995 7.2E

- 12 0.09-0 . 13 12 ± 0. 3 0 . 1 1 ± 1.0 0.998 5.IE-13 0.96 ± 0.0 1 4 ± 12 8 4.5557 pH 8 . 3) Desorption Gold en Lake Sand I. I ± 0 . 1 0 .963 9.9E-08 0 .95 -1. 9 3 35 8 ± 24 I. I ± 1.2 0 .983 0.599 0.98 ± 0 .0 3 67 ± 3 98 0.0018- ( 0. 3% 

### o c 0 . 2133 pH 8. 5) WY C l ay 1.5 4- 0 . 0004- (0 .8 % 

### o c , 3 .4 ± 0 . 6 0.82 0 0.0008 18 . 86 4 3 0 ± 7 6 2. 1 ± 2 .0 0.854 0.30 7 0. 8 3 ± 0 . 1 2 6 6 ± 246 0 .08 29 pH 8 .3 )

5 o f 29Flazasulfuron (PC 1 1 9011) MRID 49030002

A 

### Table 1 (cont) . Summary of Adsorption/Desorption Results Soil/ Regressed Kd Regressed KF l/o for Krnc Sediment, (L/kg-soil) Range of Koc (L/kg- ((L/kg

-soil> · 11") adsorption (LJkg-oc>· Ceq %0C Kd( L/kg

- OC) "") Range pH Value± p -value soil) Value± 

# I Value ± Value ± (mg/ L) SE r2 Value± S E SE ri p - value S E SE DTPU Adsorption Golden Lake Sand 0.42 ± 0 .0 0.989 4.4E-10 0.38-0 . 76 1 40 ± 5 0 . 50 ± 1.0 0 . 998 l. lE-09 0 . 87 ± 0 .0 166 ± 341 0.0294- (0 . 3% 

## oc 3.6445 pH 8.5) WY C l ay 0.0299- (0 . 8%0C , 0 . 63 ± 0.0 0.997 5.2E-1 3 0.61-0.75 79 ± l 0.67 ± 1.0 0.999 4 .2E -08 0 . 97 ± 0 .0 83 ± 128 3.14 74 pH. 8 . 3) Desornti on Golden Lake Sand l.9 ± 0.1 0 .991 l.4 E- 10 1. 74-3.62 631 ± 20 1.7±1.1 0.997 6.4E-06 0.85 ± 0 .0 562±351 0.0047-

. (0.3% 

## oc 0 . 5084 pH 8.5) WY Clay 0.0034

- (0 . 8%0C, 4 .5 ± 0 .2 0 .977 l.2E-08 4.18-7.45 557 ± 29 5.0 ± 1.1 0 .986 2 . 7E-06 0 . 98 ± 0 .0 619 ± 14 4 0 . 3692 pH 8.3)

6 of29Flazasulfuron (PC 11901 1) MRID 49 0 3 0002



### Table 1 (cont) . S ummary of Adsorption/Desorp tion Resu lt sA Soi l / Re gre sse d Kd R egresse d KF l/ n for K Fo c Sediment , (L / kg-soil) Range of Koc (L/kg- (( L/ kg-so ii>" 1 1 ") adsorption**(L/k~-OC }-**  Ceq %0C l<o(L / kg

- OC) I") Range pH Value ± p-va lue so il) Value± 

# I Va lue ± Value± (mg/L) 

### SE rz Value± SE 

### SE r z p-value 

### SE SE DTPP Ad so rp t io n Go lden Lake Sand 5.0 ± 0.2 0.988 5. 9E-IO 4.02- 1679 ± 62 5.9 ± l.O 0.994 l.3 E- 10 0.81 :I: 0.0 1980 ± 348 0.0206- (0.3% 

### oc 13.31 3.387 9 pH 8.5) WY C l ay 8.41- 0 .0 106- (0 . 8% 

### oc , 9. 1 ± 0.6 0.968 5.lE-08 35.31 1140 ± 69 11.8 ± l.l 0.973 7.4E-09 0.74 ± 0.0 1473 ± 138 2.73 15 pH 8.3 ) Desorption Gold e n Lake Sand 41.7 ± 0 .9 0 .995 7.I E-12 39.91- 1 3898 :I: 3 1 2 37 .7 ± 1.0 0.999 7.3E-l4 0 .91 ± 0 .0 125 57 ± 0.0034- (0 .3% 0 C 63 . 50 3 45 0.3412 pH 8 .5) WY C l ay 85.81

- 0 .002- ( 0 . 8 % 0C , 9 2.7 ± 4 .5 0 .9 7 9 7.0 E-09 1 77.2 5 I 15 8 3 ± 5 6 2 7 7.6 ± I.I 0.992 I.OE-IO 0 . 88 ± 0 .0 9 7 03 ± 139 0.2481 pH 8 .3)

7 of29Flazasulfuron (PC 119011) MRID 49030002


### Table 1 (cont). Summary of Adsorption/Desorption Results A Soil/ Regressed Kd Regressed Kr l/n for KFoc Sediment, (L/kg

- soil) Range of Koc (L/kg- ((L/kg-soi1>- 1'") adsorption (L/kg-oc>- Ceq %0C Kd(L/kg

- OC) l/n) Range pH Value± p-value soil) Value± 

### I Value± Value± (mg/L) 

### SE 

### r2 Value± SE SE rz p -value SE SE ADMP Adsorption Golden Lake Sand 0.39 ± 0 .0 0.935 l.2E-06 0.30

- 1.18 130 ± 11 0 . 55 ± 1.1 0.983 2.6E-05 0.79 ± 0.0 184 ± 357 0.0225- (0.3%0C 3.8756 pH 8.5) WY Clay 2.86- 0.0064- (0 . 8%0C, 3.2 ±0.3 0.919 3.3E-06 26.56 400 ± 40 5.0 ± 1.1 0.983 2 . 8E-08 0.64 ± 0.0 628 ± 135 2.9165 pH 8.3) Desorption Golden Lake Sand 5.3 ± 0.5 0.943 3.0E- 06 4.89- 1764 ± 153 4.5 ± 1.3 0.967 0.0003 0.87 ± O.l 1497 ± 419 0.002- (0.3%0C 12.52 0.25 29 pH 8.5) WY C lay 12 . 93- 0.0022- (0.8%0C, 14.8±1.5 0.918 3.5 E- 06 74 .7 3 1845 ± 184 13.l ± 1.3 0.927 4.3E-06 0.67 ± 0 . 1 1632 ± 158 0.4941 pH 8.3) Abbrev1at10ns : SE = standard error of regression. A Data were obtained from Appendix G, pp . 203

-204; Appendix H, pp. 212-213; Appendix I , pp. 221-222 ; Appendix J, pp . 232-233; and Appendix K, pp. 241- 242 of the study report. Data and results are in the attached Excel workbook . See Attachment 3 for equations used for calculations .

8 of29Flazasu I furon CPC 11901 I) MRID 49030002 I. Material and Methods A. Materials 1. Test Material : [ 14

### C]-labeled flazasulfuron (SL -160 ; p. 18; Figure 1 , p. 75; Figure 2, p. 76; Appendix B , p. 140) Batch/Lot number: CP -138 5-2 Specific radioactivity: 4.18 MBq/mg Radioc hemical purity: >93% Chemical purity: Not reported Solubility in water: Not reported Structure N 

### ft

### ~**N~ ·**  o- c H , 

# $ -N N-<**~** II I I 14- o H H 0 - Cll, F 

## (1 4 

### C]

- labeled TPSA (p . 18; Figure 1 , p. 75; Figure 2, p. 77; Appendix B , p. 142) · Batch/ L ot number: CP-3082 Specific radioa ctivity : 9.15 MBq/mg Radiochemical purity: >99% Chemical purity: Not reported Solubility in water: Not reported Structure:

# ~:**~** 

# ..**o** N**~** H 

### ll"w ........ o 

### I H [ 14

### C]-labeled DTPU (p. 18 ; Figure 1 , p. 75; Figure 2, p. 78; Appendix B , p. 146) Batch /Lot number: CP-3083 Specific radioactivity: 5.63 MBq/mg Radiochemical purity: >98% Chemical purity: Not reported Solubility in water: Not report ed Structure:

9of29

### Flazasulfuron**(P~** 119011) MRID 49030002 ( 14

### C]-Iabeled DTPP (p. 18; Figure 1, p. 75; Figure 2, p. 7 9 ; Appendix B, p. 144) Batch/Lot number: CP-3084 Specific radioactivity: 6.42 MBq/mg Radiochemical purity: >99% Chemical purity: Not reported Solubility in water: Not reported Structure:

[Pyrimidine-5- 14

### C)

- labeled ADMP (p . 18; Figure 1, p . 75 ; Figure 2, p. 80; Appendix B, p. 148) Batch/Lot number: CP-3085 Specific radioactivity: 10.4 MBq/mg Radiochemical purity: >99% Chemical purity: Not reported Solubility in wa t er: Not reported Structure: · O-CH3 

# "'-1---1---( 

# H N=<

O-CH 3

10of29Flazasulfuron (PC 119011) 

### MRID 49030002 

### 2. Ref erenee Compounds: Flazasulfuron (SL-160; p. 18; Appendix B, p. 141) Ba tch/Lot number: Y-920205 Purity: l 00% ADMP (p. 18; Appendix . B,p . 149) Batch/Lot number: Y-Ba.79 Purity: 100% DTPU (p. 18; Appendix B, p . 147) Batch/Lot number: 0205 Purity: 98.5% DTPP (p. 18; Appendix B, p. 145) Batch/Lot number: 0205 Purity: 98.3% TPSA (p. 18 ; Appendix B, p. 143) Batch/Lot number: 0205 Purity: 100% 3 . 

### Soils/Sediment: The study was conducted using one sediment and one soil (p. 21; Ta b le II, p. 45). Pesticides use history at the collection sites was not reported. The soils were sieved (2 mm) and stored in plastic bags . A summary of the physical and chemical properties of the soils is provided in 

### Table 

### 2 usi ng US DA Soil Taxonomy. 

### T bl 2

D a e 

# . escnption o

## rs ·11s d' Ol 

### e 1ment Soil Name Golden Lake Sand WY Clay Origin Steele, North Dakota Fremont Co . , Wyoming USDA T extural Class Sand Clay %Sand 95 25 %Silt 2 28 %Clav 3 47 %0C 0.3 0 . 8 CEC (meq/100 g) 8.0 28.6 pH in w ater (1: 1) 8.5 8.3 oH (0.0 l M CaCh) 8.2 NR % mois t ure (1 / 3 bar) 4.7 28.8 Soil Tax onomy NR NR CaC03 e quivalence NR NR Data were obtained from Tab le II, p. 45 and Appendix C, pp. 150-151 of the study report. NR = n ot reported. 

### B . Stu d y design 

### 1. Experimental conditions: Preliminary tests were conducted to examine the appropriate soil:solution ratio (Tier I) and equilibration times to be used in the definitive test (Tier 2; pp . 22-26). 11 of29Flazasulfuron (PC 11 90 11) 

### MRID 4 9 030002

For Tier 1 tests, aliquots of Golden Lake sand and WY clay soils were prep ared in O.OlM CaCh solution at soil:solution ratios of 1: 1, 1 :5, and 1 :25 (w:v; pp. 22-23) . The solutions were then dosed with 

## [1 4 C] -labeled :flazasulfuron , TPSA , DTPU, DTPP, and ADMP at 

### ca. 5 mg/L. Soil-less controls and blank samples were also prepared. The flazasulfuron test . was also conducted at a soil:sol. ution ratio of 5:4 (w:v). The samples were maintained in the dark at 25°C. After 24 hours of shaking, triplicate aliquots were analyzed using LSC. Based on the results , a soil:solution ratio of 1: 1 (w:v) was selected for [ 14C]-labeled flazasulfuron , TPSA, and DTPU treated soils, 

### 1 :10 (w:v) was selected for [ 14C]DTPP treated so il s, and 1 

### :1 (w:v; Golden Lake sand) and 

### 1:4 (w:v; 

### WY clay) were selected for [ 14C]ADMP treated soils (p . 32; Table V, p. 52) . For Tier 2 tests, aliquots of Golden Lake sand and WY clay soils were prepared in O.OlM CaCh solution at soil : solution ratios of 1: 1, 1:4 or 1: 10 (w:v; pp. 23-26). The solutions were then dosed with [ 14C]-labeled flazasulfuron, TPSA, DTPU , DTPP, and ADMP at 

### ca. 5 mg/L. Soil-less controls and blank samples were also prepared. The samples were maintained in the dark at 25°C. After 

### ca . 4, 6 , 24, 29, and 48 hours of shaking, triplicate aliquots of [ 14C]-labeled TPSA, DTPU, DTPP, and ADMP adsorption solutions were analyzed using LSC. Aliquots of the remaining soils were combusted and analyzed. For flazasulfuron, the test w as terminated after 30 hours of shaking due to instability of the test substance . Triplicate aliquots of the adsorption solutions were analyzed using LSC, and aliquots of the remaining soils were combusted and analyzed. Aliquots of the soils treated at the highest test concentration were extracted three times with acetonitrile:water (9: 1, v:v) prior to HPLC analysis. Due to instability of flazasulfuron in solution, an equilibrium time of 24 hours was selected for the definitive study (p. 33). For the remaining samples, 24 hours was selected for soils treated with TPSA and DTPU and 48 hours was selected for soils trea ted with DTPP and ADMP. For the definitive study, duplicate aliquots of each soil were pre-equili brate d overnight with 0 . 01 M CaCh solution (pp. 26-27). Soil: solution ratios were 1: 1 (w:v) for [ 14C]-labeled flazasulfuron, TPSA, and DTPU treated soils, 1: 10 ( w:v) for [ 14C]DTPP treated soils, and 

### 1: 1 (w:v; Golden Lake sand) and 

### 1 :4 (w:v; WY clay) for ( 14C]ADM P treated soils . Additional duplicate soil-less control s amples were prepared at the highest test concentration. Following pre-equilibration, the samples were dosed to give nominal concentration ranges of 0.05 to 

### 5 mg/ L and shaken in the dark at 25°C for 24 hours (flazasulfuron, TPSA, and DTPU t reated soils) or 48 hours (DTPP and ADMP treated soils). Following centrifugation, the supematants were decanted and analyzed. An equivalent volume offresh sterile O.OlM aqueous CaCl2 was added to each test vessel and the samples were equilibrated in the dark at 25°C as spec ified for the adsorption phase. The s amples were centrifuged and the supematants were decanted and analyzed. Aliquots of 

### the remaining soils 

### were combusted and analyzed. Aliquots ofthe soils 

### trea ted at the highest test concentration were extracted three times by shaking with
12of29Flazas ulfuro n (PC 119011) MRID 49030002 acetonitrile :wa ter (9: 1 , v:v) prior to analysis. 2. 

### Analytical procedures: Radioactivity in the aqueous supematants was determined by Liquid Scintill ati on Counting (LSC; pp. 20 , 26-27). Desorption supematants and soil extracts collected from soi ls treated at th e high est test concentration were analyzed for flazasulfuron using HPLC (Alltech Alltima AQ C-18, 5 μm co lumn , gradient mobile phase of (A) l % phosphoric acid in HPLC water and (B) l % phosphoric acid 

### in acetonitrile, with UV (240 nm) and radioacti ve flow detection; pp. 20-2 1 , 27-2 8). The Limit of Detection (LOD) for LSC analysis was 0.00028 ppm fo r 0.05 ppm dose samples (p. 28). The L OD for combu stio n sam p les was 0.00063 ppm. T he LOD and Limit of Quantification (LOQ) for HPLC analysis were 0.006 μgig and 0.003 μg /g, re spectively (p. 29). 

### II. Re sults and Discussion A . 

### Mass Balance: F or [ 14C]flazasulfuron tre ated soils, recovery ranged from 96.2

- 1 01.0 % of the app lied for Golden Lake sand and l 00.2- 111.6 % for WY clay (p. 34; Table V II , p. 58). For [ 14C]TPSA treated soils, recovery ranged from 97.3-98.5% of the applied for Golden Lake s a nd and 97.6-101.1 % for WY clay (p . 34; Tab le VIII, p . 59). For [ 14C] DTPU treated s oils , recovery ranged from 92.1

- 99.1% of the appl ied for Golden Lake sand and 91.3-95.6% for WY clay (p. 3 4 ; Table IX , p. 60). For [ 14C] DTPP treated soils, recovery ranged from 87.5-104.0% o f the applied for Golden Lake s and and 88.4-190.1% for WY clay (p . 34; T able X , p. 61). For [ 14C]ADMP treated soils, recovery ranged from 92.4-99.9% of the applied for Go lden Lake sand and 8 1. 8-99 . 3% for WY clay (p. 34; Ta bl e XI , p. 62). 

### B. Transformation of Parent Compound: HPLC analysis of test so il s treated at the highest test concentration (5 mg/L) showed that [ 14C ] flazasulfuron w as unstable in both test soil s with DTPU , STPP , and ADMP present as major degradates in each instance (p. 34; Fi gure 5 , pp. 87-9 3). Due to this instability, equilibrium concentrations were adjusted based o n the percent flazasulfuron determine d by HPLC anal ysis of each phase (p. 35). [ 14C]-labeled TPSA, DTPU, DTPP , and ADMP were shown to be s table in both test soils treated at the highest test concentration and 

### in control solutions for the duration of the study (Figures 6-9 , pp. 94- 1 17). C . 

### Find ings: Reported values were calculated using linear regression (Excel) and the equations and m e thods discussed in the calculations section. Equilibratio n concentrations 

### in water were appropriate for all [ 14C]-labeled flazasulfuron , TPSA, DTPU , D T PP , and ADMP treated so il s, ranging from 0.0064-4.5557 μg/mL following the adsorption phase and 0.0004-0.5084 μg/rnL following desorption 13 of29Flazasulfuron (PC 11901 1) MRID 49030002 

### (Appendix G, pp . 203-204; Appendix H , pp. 212-213; Appendix I, pp. 221-222; Appendix 

### J, pp. 232-233; and Appendix K, pp. 241

- 242) . Percent adsorption and p ercent desorption, as percent of the adsorbed, were not determined. Coefficients of variation (CV) ranged from 0 .02 to 1.1 and 0.2 to 0.8 across all [ 14

### C]-trea te d soi l s for adsorption K F 

### and K F oc, 

### respectively , and 0.03 to 0.7 and 0 . 1 to 0.6 across all ( 14

### C]-treated so ils for desorption KF 

### and KFoc , 

### respectively (DER Attachment). 

### T bl 3 D

a e . escrmtlon o 

### fAd f 

## c ffi . t sorp ton oe 1c1en s Soil 

### I Kd (L/kg) 

### I Koc 

### I KF (L/kg) 

### I K F oc (1 4 C )Flazasulfuron Golden Lake Sand 

### I 0.20 

### I 67 

### I 0.23 

### I 77 WY Clay 

### I 0 . 10 

### I 12 

### I 0.16 

### I 20 [ 14C]TPSA Golden Lake Sand 

### I 0 . 10 

### I 35 

### I 0 . 11 

### I 35 WYClav 

### I 0.10 

### I 12 

### I 0.11 

### I 14 [ 14C]DTPU Golden Lake Sand 

### I 0.42 

### I 140 

### I o.5o 

### I 166 WY Clay 

### I o . 63 

### I 79 

### I o.67 

### I 83 [ 1 4 C]DTPP Golden Lake Sand 

### I 5 .04 

### I 1679 

### I 5.94 

### I 1980 WYClav 

### I 9.12 

### I 1 140 

### I 1 t.78 

### I 1473 

## r' 4 ClADMP Golden Lake Sand 

### I o.39 

### I 130 

### I o.55 

### I 184 WY Clay 

### I 3 .20 

### I 400 

### I 5.03 

### I 628 

### T bl 4 D

a 

### e 

# . f 

### D escr1pt10n o esorphon 

## c ffi . oe 1c1ents Soil 

### I Kdes (Lf.kg) 

### I Koc-des 

### I KFdes (L/kg) 

### I K Foc-ges ( 1 4 C]Flazasulfuron Golden Lake Sand 

### I 0.92 

### I 308 

### I o.89 

### I 298 WY Clay 

### I 1.17 

### I 146 

### I o.93 

### I 116 

## r 14 ClTPSA Golden Lake Sand 

### I 1.08 

### I 358 

### I uo 

### I 367 WY Clay 

### I 3.44 

### I 430 

### I 2.13 

### I 266 [' 4 C]DTPU Golden Lake Sand 

### I 1.89 

### I 631 

### I 1.69 

### I 562 WYClav 

### I 4.46 

### I 557 

### I 4.96 

### I 619 ( 1 4 C]DTPP Golden Lake Sand 

### I 41.69 

### I 13898 

### I 37.67 

### I 1255 7 WY Clay 

### I 92.67 

### I 11583 

### I 77.63 

### I 9703 

## r 14ClADMP Golde n Lake Sand 

### I 5.29 

### I 1764 

### I 4.49 

### I 1497 WY Clay 

### I 14 . 76 

### I 1845 

### I 13 .06 

### I 1632 

### Reviewer-reported Freundlich sorption coefficients were mostly in agreement with the study-reported values (Tables XII-XXIII, pp. 63- 74; Figures 10-19, pp . 1 ] 8-127). There were a few reviewer-reported values tha t differed slightly from study-r eported values due to rounding errors. Since only two types of soils were used for the test, regression**of~** 

### by percent organic carbon, CEC, and percent clay was not valid.

14 of29Flazas u lfuron (PC 119011) 

### MRID 49030002 

### T b l 

### 5 S

a e**.** f 

### R ummary o ef!ressed Kd 0 A 

## oc CEC d 0 A 

### Cl vs 0 

### ' , an 0 

### ay Parameter 

## r p-value Kd vs . % organic carbon N IA NIA Kd VS . C EC Kd vs . % clav 

### Ill . St u dy Deficiencies and Reviewer's Comments The fo ll owing deviations were noted: 1 . The study was conducted using the parent compound flazasulfuron, as well as four transformation products. 2 . The posit ion of the radiol abe l for the test substance flazasulfuron was different in the chemical structures provided in the study report (pp. 75 and 129; Appendix B, p. 140). The position of the radiolabe l for the test substances D T PU and DTPP were al so different in the chemical structures provided (pp. 75 and 129). In addition, the chemical structures for ADMP and TPSA presented in Figure 1 , p. 7 5 of th e study report were reversed . 3 . The study was conducted using only two types of soi l s. 4 . The parent compound was found to be highly unstable in solution, with significant degradation. Using th e McCall Cl assifica t ion scale, the study author predicted the following: 

### Tab le 6. Summary of Mobility Classificat ion , based on M cCall et.al. Tre atme.nt Golden Lake Sand WY Clay 

## r 1 4 ClFlaz.as ulfuron Hi!ili Very high [' 4 ClTP S A Very high Very high 

## r 1 4 ClD T P U Medium High 

## r' 4 ClDT PP Low Low [' 4 C]ADMP Medium Low Data we re obtained from pp . 41

- 42 ofthe study report . 

### I V . Refe rences I. 

### U. S . Environmental Protection Agency. 2008. Fate, Transport and Transformation Te st Guidelines, OPPTS 835 . 1230, adsorption/desorption (batch equilibr ium). Office of Prevention, Pesticides and T oxic Substances, Washingt on, DC. E PA 712

- C

- 08- 01 9 .

15of29F l azasulfuron (PC 119011) MRID 49030002



### DER ATTACHMENT 

### 1. Table 1. F laz as ul furo n and Its Environmental T ransform ation Products. A 

### Code Name/ ' 

### StUdy Maximum Fin a l o/oAR Chemical Name Chemical Structure MRID Synonym Type %AR(day) (study le ngth ) PARENT F lazasulf uron IUPAC: l-(4 , 6
- 

### ( SL -160) D imethoxypyrimidin-2-yl)- 3-(3-trifluoromethy l-2- pyr i dyl sulfonyl)urea CAS : N -[[(4,6-dime thoxy- 2-

# ~~--~--<~**CH 3**  pyrimidinyl ) ami no ]carbonyl ] -3-(trifluoromethy l)-2- 835. 1230 pyridinesulfonamide

## ~ 

# ! ! N
- . Ba tch 49030002 NA 

### NA equilibrium CAS No. : 104040

-78-0 

# · 0

-CH3

F Formula: C 13 .H 12F3NsOsS MW : 407.3 g/mo l SMILES: n I cccc( C(F)(F)F)c I S( =0) (= O) NC(= O )Nc2nc( OC)cc(OC)n2 

### MAJOR(>10%) TRANSFORMATION PRODUC TS N o major transformation products were identified. 

### MINOR (<10%) TRANSFORMATION PRODUCTS No minor transformati on products were iden t ifi e d . 

### REFERENCE COMPOUNDS NOT IDENTIFIED 

## . A ll compounds used as reference compounds were identified. A " . . " " " " "

AR means applied rad 1o act1v1ty . MW means m olecula r weight . NA means not applicable .

16 of29Flazasu l furon (P C 1 190 1 1) MRID 49030002



### Table 2. DTPU and Its E nvironmental Transformation P roducts. " Code Name/ Chemical Name Chemical Structure Study MRID 

### Maximum Final %AR Synonym**Type ~**  

### %AR(day) (study l ength) PARENT 

### DTPU I UPAC: 1- (4 , 6- D imet hoxyp yrimidin- /CH 3 2-yl) -1

- [ 3-(trifluorometh y l)-2

- 0 pyridy l]urea F F

' Form u la: C13 H 12F3Ns03 

## 7 

# I**~** 

# I MW: 34 3.2 6 g/ m

o l

# >~. 835.1230 S MILES:**~** Ba tch 490300 0 2 NA 

### NA COc I cc( nc(n I )N(c2c(cccn2)C(F)(F)F N 0 equilib r ium )C(= O) N)O C 

# ",.Ao I CH 3 

# I H 

### MAJOR (>10%) TRANSFORMATION PRODUCTS No ma j or transformation product s wer e identified. 

### MINOR (<10%) TRANSFORMATION PRODUCTS No minor tran sfo rmati on pro du c ts were identified. 

### REFERENCE COMPOUNDS NOT IDENTIFIED A ll compounds u se d as refere nce co mpound s were identified. A " .. " " ,, II II

AR means applied rad1oac11v1ty . MW m eans molecular weight . NA means not app li cab l e .

17 of29Flazasulfuron (PC 119011) 

### MRID 49030002



### Table 3. DTPP and Its Environmental Transformation Products. A 

### Code Name/ CbemicaJ Name Chemical Structure Study MRID Maximum Final %AR Synonym

- 

### Type %AR(day) (study length) PARENT DTPP IUP AC : 4 , 6-Dimethoxy-2-(3- /CH 3 trifluoromethyl-2- 0 pyridylamino)pyrimidine F F Formula: C12H11f3N402**~** N ::;/" 835.1230 MW : 300.24 g/mol 

# I 

# :A I Ba tch 49030002 NA NA SMILES:**~** equ ilibrium COc I cc(nc(n 1 )Nc2c(cccn2)C(F)(F)F) N 0 

## oc 

# I I H CH 3 

### MAJOR (>10%) TRANSFORMATIO N PRODUCTS No major transformation products were identified. 

### MINOR (<10%) TRANSFORMATION PRODUCTS No minor transformation products were identified. 

### REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A " . . , , " " " "

AR means applied rad1oact1v1ty . MW means molecular weight . NA means not applicable .

18 of29F l azas u lfu ron (PC 11901 l) MRID 49030002



### Table 4. ADMP and Its Environmentai T ransformation Products . A 

### Code Name/ Chemical Name Chemical Structu r e Study MRID Maximum Final 

### o/oAR Synonym Type %AR(day) (study l ength) 

## PARENT ADMP I UPA C : 2-Amino

-4 , 6- d imethoxypyrimidine 

### .

# H'N-1~-C**H3** F ormula: C 6 H9N3 0 2 835.1230 MW : 155. 15 g/ mol SM ILES: COc l cc(nc(n l )N)OC Batch 49030002 NA NA 

## I - equilibrium H N 

### 0-CH 3 

### MAJOR (>10%) TRANSFORMATI ON PRODUCTS

. N o major transformation products were identified.

. 

### MINOR (<10%) TRANSFORMATION PRODUCTS No m inor transformation products were id ent ified. 

### REFERENCE COMPOUNDS NOT IDENTIFIED A ll compou n ds used as reference compounds were identified. A " . . '' " ,, " "

AR means appli ed rad1o activ1ty . M W mean s molec u lar we i ght . NA means not applicabl e .

19 of29Flazasulfuron (PC 119011) MRlD 49030002



### Table 5. TPSA and Its Environmental Transformation Products. A 

### Code Name/ Chemical Name Chemical Structure Study MRID Maximum Final o/oAR Synonym Type %AR(day) (study length) PARENT TPSA IUPAC: 3-Trifluoromethyl-2- pyridinesulphonamide 

# oc: Formula: C6H5f3N202S MW: 226.18 g/mol 835.1230 SMILES: 0 Batch 49030002 NA NA N 

# s?' H c Icc{ c(nc I )S(=O)(= O)N)C(F)(F)F 

# I f''w"'..--- equ ilibrium o 

# I H 

### MAJOR(> 10%) TRANSFORMATION PRODUCTS No major transformation products were identified. 

### MINOR (<10%) TRANSFORMATION PRODUCTS No minor tran sformation products were identified.



### · REFERENCE COMPOUNDS NOT IDENTIFIED A ll compounds used as reference compounds were identified. A " .. ,, " ,, " "

AR means applied rad1oactiv1ty . MW means molecular weight . NA means not applicable .

20 of29Flazas uI fu ro n (P C 1 190 I I) 

### MRID 49 0 3 0 00 2



### D

E R A T TACHMENT 1. 

### Table 1. 

### Flaza sulfuron and Its Environmental Transformation Products . A 

### C od e N ame/ Study r 

### Maxi mum F inal 0 

### A>AR Chemical Name Chemical Structure IMRID Synonym Type %AR(day) (study length) PARENT Flaza s ulfuron IUPA C : 1-(4,6

- (SL- 1 60) Dimethoxypyrimidin

2-yl)-3-(3- trifluoromethyl-2- pyridylsulfooyl)urea CAS: N-1((4,6- dimethoxy-2- pyrimidinyl)amino)car O

# ~**-CH3** bonyl)-3- N 

## II N 

### 835.1230 (trifluoromethyl)-2-

# S-**N** 

# N -<**~** Batch 4903000 NA NA pyridines ulfonamide 

## II I I 

# N- equilibriu 2 0 H H . O-CH 3 

### m CAS No.: 104040-78-0 F 

### Formula: C13H12F3N sO sS MW: 407.3 g/mol SMILES: nlcccc(C(F)(F)F)clS(= O)(=O)NC(= O)Nc2nc( OC)cc(OC)n2 MAJOR (>10%) TRANSFORMATION PRODUCTS No major transformation products were identified. MI NOR (<10%) TRANSFORMATION PRODUCTS

21 o f 29Flazasulfuron (PC 119011) MRID 49030002


### Code Name/ Chemical Name Chemical Structure Study MRID Maximum Final %AR Synonym T ype %AR(day) (study length) No minor transformation products were identified . REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A 

## " 

# . . " 

## " 

# . " " "

AR means apphed radroachv1ty . MW means molecular weight . NA means not apphcable .

22 of29Flaza s ulfuro n (P C 1 1 901 1) MRJD 49 03 000 2



### Ta bl e 2. DTPU a n d Its E n vironmen t al Transformation Products . A 

### Code Name/ Chemical Name Chemical Structure Study MRID Maximum Final 0 

### /oAR Synonym Type %AR(day) (study length) PARENT DTPU IUPAC: 1-(4,6- / CH 3 

### Dimethoxypyrimidin-2-yl)

- 1- 0 

### [3-(trifluoromethyl)-2- F F 

### pyridyl]urea**~** N ::/"' 

### 835.1230 Formula: C13812F3Ns03 :::::-.... 

# I 

# :A I Batch 4903000 NA NA MW: 343.26 g/mol N 0 

### equilibriu 2 SMILES: 

# " , .Ao I m C0clcc(nc(nl)N(c2c(cccn2)C C H 3 

### (F)(F)F)C(= O)N)OC 

# I H 

### MAJOR (>10%) TRANSFORMATION PRODUCTS No major transformation products were identified. MINOR (<10%) TRANSFORMATION PRODUCTS No minor transformation products were identified. REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A 

### . 

## ..

AR means "applied radioactivity". MW means " molecular weight". NA means "not applicable" .

23 o f 29Flazas u l furon (PC 1190 1 1) 

### MRID 49030002



### Tabl e 3 . 

### DTPP and Its Environmental Tra nsformation Products. A 

### Code Name/ Chemical Name Chemical Str u cture Study MRID Maximum Final %AR Synonym Type %AR( d ay) (study length) PARENT DTPP IUP AC : 4,6

-Dimethoxy-2-(3

- trifluoromethyl-2- /CH 3 

### pyridylamino)pyrimidine 0 F F 

### 835.1230 Formula : C12 H 11F3N402**~** N :;:/' 

### Batch 4903000 MW: 300 . 24 g/mol 

# I 

# :A I equilibriu 2 NA NA SMILES:**~** 

### m N 0 

### COclcc(nc(nl)Nc2c(cccn2)C( 

# I I F)(F)F)OC H CH 3 

### MAJOR (> 1 0%) TRANSFORMATION PRODUCTS No major transformation products were identified . MINOR (<10%) TRANSFORM ATION PRODUCTS No minor transformation products were identified. REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A 

## " 

# .. " 

## " I 

## "

AR means apphed rad 1 oachv 1 ty . MW means molecu lar we ight". NA means ' not app hcable .

24 o f 29Flazas ulfu ro n (P C I 190 I I) MRJD 49030002



### Table 4 . ADMP and Its Env ironmental T ransformation P roducts. A 

### Code Name/ Chemical Name Chemical Structure Study MRID Maximum Final 0 

### /oAR Synonym Type %AR(day) (study length) PARENT ADMP 

### IUP AC: 2-Amino-4,6- dimetboxypyrimidine

# H'**N--<!~ 0-C** **3** 

### Fo r mula: C6H9N302 835.1230 Batch 4903000 MW: 155.15 g/mol equilibriu 2 NA NA SMILES: 

## I - H N 

### COclcc(nc(nl)N)OC m O-CH 3 

### MAJOR (>10%) TRANSFORMATION PRODUCTS No major tr ansformation products were identified. MINOR (<10%) TRANSFORMATION PRODUCTS No minor tr ansformation prod ucts were identified. REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A 

## " 

## . . " " " 

## . I



### AR means apphed rad10achv1ty . MW means molecular weight". NA means not applicable' .

25 of29F lazasulfuron (PC 119011) MRID 49030002



### Table 5. TPSA and Its Environmental Transformation Products. A 

### Code Name/ Chemical Name Chemical Structure Study MRID Maximum Final %AR Synonym Type %AR(day) (study length) PARENT TPSA IUPAC: 3-Trifluoromethyl

- 2- pyridinesulphonamide 

# oc: Formula: C6HsF3N202S 835 . 1230 MW: 226 . 18 g/mol 0 

### Batch 4903000 NA NA SMILES: N 

# s? H 

### equilibriu 2 cl cc( c(ncl)S(=O)(=O)N)C(F)( 

## I f''w',,. m F)F o 

# I H 

### MAJOR(>10%) TRANSFORMATION PRODUCTS No major transformation products were identified. MINOR (<10%) TRANSFORMATION PRODUCTS No minor transformation products were identified. REFERENCE COMPOUNDS NOT IDENTIFIED All compounds used as reference compounds were identified. A 

## " 

# .. " " 

## . " " 

## "

AR means apphed radt0acttv1ty . MW means molecular weight . NA means not applicable .

26 of29FlazasuJfuron (PC 119011) MRID 49030002 

### Attachment 2: Stat i stics Spreadsheets and Graphs

27 of29**F=la=za=s=u =fu=r=o=n~(P~C~l~l9~0~1~1).__~~~~~** **~~~~~ ~~~~~~~** **lD 030002**  

### Attachment 3: Calculations Calculations were performed by the reviewer using Excel and the following equat i ons. Ceq range is the range of test concentrations in water at equilibrium. Cs is the test concentrations sorbed to soil or sediment at equilibrium.**~** - Distribution Coefficient for Adsorption = C 5 /Ce q (eq 1) • Regressed Kd is calculated using linear regression of Cs versus Ceq with a forced zero intercept o ver the range of measured Ceq for each soil/sedi ment. • Range of Kd reflect s the range of each Kd measured at a specific concen tration i n a soil/sediment Koc -Organic Carbon Normalized Adsorption Coefficient = regressed Kd * 100/% O C (eq 

### 2) Standard Error (SE) of Ko c = Kd SE * 100 / %0C (eq 

### 3) KF -Freundlich Adsorption Coefficient and the Freundlich exponent (1 /n) were calculated using nonlinear regression of Cs = K F x Ceq 11 ". Cs should be expressed 

### in mg/kg and Ceq should be expressed i n mg/Lin the regression. (eq 4) K FOc -Organic Carbon Normalized Adsorption Coefficient = KF* 100 / %0C Standard E rror (S E ) of KF oc = KF SE * 100 / %0C (eq 5) (eq 

### 6) Ko E S

- Apparent Desorption Coefficien t = C 5/Ceq where C s and Ceq ar e measured after an initial sorption measurement and the soil/ sediment is placed in a new so lution and allowed to equilibrate, so that any material in solution desorbed from the soi l / sediment. (eq 

### 7) • Regressed KoE s is calculated using linear regression of Cs versus Ceq o ver the range of Ceq measured with a forced zero intercept for each soil/ sedime nt. • Range ofKoE s reflects the range of each KoEs measured at a specific concentration in a soil/sediment Koc
- D

ES -Organic Carbon Normalized Apparent Desorption Coefficient = regressed KoE s *100 / % OC (eq 

### 8) Standard Error o f Koc-o E s = Ko E s SE* 1 00/%0C (eq 9) K F -DE S - Freundlich Desorption Coefficient and the Freundli ch Desorption expone n t (l / n) were calculated using nonlinear regression of C s 

### = KF -D

ES x Ceq 11" ( eq 10) 28 of29Flazast lfuron CPC 1 1 9011) MRID 49030002 

### K

FOc-oEs -Organic Carbon Normalized Freund lich Desorption Coefficient= 

### Kr. D

ES * 

### 1 0 0 / %0C (eq 

### 1 1) Standard Error of K FOc-DES 

### = KF 

### SE 

## * 1 00/ %0C (eq 12)

29 of29