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

OFFICE OF PREVENTION, PESTICIDES AND TOXIC SUBSTANCES



### PC Code: 080818 DP Barcodes: 356140, 367446

Date: March 11, 2010

MEMORANDUM

SUBJECT: Transmittal Memorandum for: Environmental Fate and Ecological Risk Assessment in Support of the Section 3 Registration of the New Chemical Indaziflam (BCS AA10717)

TO: Erik Kraft, Chemical Review Manager Jim Tompkins, Risk Manager Registration Division (7505P)

FROM: Reuben Baris, Physical Scientist Alicia Korol, Biologist Environmental Risk Branch IV Environmental Fate and Effects Division (7507P )

REVIEWED BY: Thomas M. Steeger, Ph.D., Senior Biologist Marietta Echeverria, Risk Assessment Process Leader Environmental Risk Branch IV Environmental Fate and Effects Division (7507P )

APPROVED BY: Elizabeth Behl, Branch Chief Environmental Risk Branch IV Environmental Fate and Effects Division (7507P )

The Environmental Fate and Effects Divisi on (EFED) has completed the environmental fate and ecological risk assessment in support of the Section 3 registration decision on the new herbicide indaziflam (BCS AA107 17). The results of this screening-level risk assessment indicate that the proposed uses of indaziflam at a single maximum application rate of 0.125 lb a.i./acre and maximum annual application rate of 0.134 lb a.i./L pose risk to listed and nonlisted species of terrestrial plants a nd aquatic vascular plants; RQs fo r these taxa for each use pattern exceeded the listed and nonlisted speci es LOC. Based on an analysis of risk to terrestrial plants from spray drift, buffers of ~350 feet and buffe rs of ~550 feet for br oadcast applications of indaziflam would reduce RQs belo w the nonlisted and listed species LOCs, respectively, for all

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### turf and food uses. These buffers would not be protective of all listed and nonlisted species for the other proposed broadcast uses of indaziflam, but they are expected to reduce the number of species ultimately affected. Proposed uses of indaziflam also pose risk to listed nonvascular plants, with RQs only slightly exceeding the LOC for home lawn and ornamental uses. Based on lack of data or inadequacy of data, chronic risk to estuarin e/marine invertebrates and birds resulting from indaziflam use is presumed. De tails regarding the environmental fate, ecological effects and ecological risk s associated with the pr oposed uses of indaziflam can be found in the executive summary of the attached document.
Data Gaps

The available environmental fate and tran sport data for indaziflam are considered complete and adequate for risk assessment purposes. The submitted toxicity studies for evaluation of environmental effects are consid ered adequate for risk assessment purposes, however the suite of data is incomplete with one identified data gap. An estuarine/marine invertebrate life cycle toxici ty study, OPPTS 850.1350, was not submitted but is required since indaziflam was demonstrated to be “highl y toxic” to estuarine/marine organisms, EC 50 

### = 0.1-1 mg/L. Given the proposed turf uses of indaziflam , it is reasonable to assume that indaziflam could move into an estuarine/marine environmen t. Chronic ecological ri sk to this taxon is unknown and thus risk is presumed. The remaining toxicity studies with th eir classifications are presented in Table 1, which identifies the status of ecologi cal effects study requirements, and Table 2, which identifies the status of environmental fate and transport study requirements

. Uncertainties An area of considerable uncertainty surrounds the potential ecologi cal chronic risk to birds. Current data on Mallard duck were inadeq uate to derive a definitive NOAEC or make a definitive determination of risk. At the lowest levels tested from repr oductive studies on Mallard duck, effects were observed on male body weight, female body weight, and food consumption. An additional avian reproduction study on Mallard duck (OPPTS 850.2300) would reduce uncertainty and may obviate the need to assume risk to this taxon.

There is also considerable uncertainty associated with the modeled aquatic exposure resulting from hardscape and residential (hom e lawns and ornamental) uses. A number of assumptions were made in the modeling of these us es and may not represent actual use patterns. For example, the use on hardscapes and lawns may be a spot treatment and all lawns in a watershed may not be simultaneously treated. To the extent that actual use patterns differ from modeling assumptions, actual envi ronmental concentrations coul d be lower. Proposed label language is ambiguous and can be mi sinterpreted leading to misapp lications. For example, label instructions that require use onl y as a spot treatment in cracks and crevices of hardscapes (driveways, sidewalks, patios), as opposed to br oadcast applications would reduce the potential aquatic exposure estimates. Fu rther, adding label language that specifies the definition of hardscapes on the BCS AA10717 20WSP label woul d also reduce uncertainty in exposure estimates.

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### Additionally, degradates of indaziflam, specifically fluoroe thyldiaminotriazine, are much more mobile than the parent, and data show th at they persist in the environment under aerobic and anaerobic conditions. Field studies indicate th at degradates of indaziflam residues may leach to ground water; fluoroethyldiaminot riazine was detected at deeper depths in the field studies compared to the other degradates. A pros pective ground water study (PGW) would help to characterize the magnitude and extent of the potential ground water contamination.
Labeling Recommendations The following recommendations are relevant to the Lawn 3FL formulation and the BCSAA10717 20WSP labels.

• On all Lawn 3FL formulations, proposed labels state, “Use on established southern lawns only.” This label language is vague and ambiguous regard ing the potential use sites. Specifying states that permit use of indaziflam will spatially reduce the potential exposure.

• On the Lawn 3FL Herbicide Concentrat e formulation (PART C: Ornamentals & Hardscapes), label language that specifies us e only as a spot treatment in cracks and crevices of hardscapes (driveways, side walks, patios), as opposed to broadcast applications would reduce th e potential aquatic exposure estimates. We recommend replacing existing text in the “where to use” box under the “quick facts”:
Use only as a spot treatment in cracks and crevices of hardscapes such as patios, sidewalks, driveways, pathways, gravel areas, and along fence lines. Do not apply as broadcast application.

• On the BCS AA10717 20WSP formulation:
o In the Non-selective Non-Crop Uses sect ion, label language that specifies use only as a spot treatment in cracks an d crevices of hardscapes (driveways, sidewalks, patios), as opposed to br oadcast applications, would reduce the potential aquatic exposure estimates. For example:
For long term control of annual weeds in non crop areas including patios, walkways, and other hardscapes, use spot treatments of BCSAA10717 20 WSP Herbicide at 3.5-7.1 oz per A ...For difficult-to-control weeds, more extended control, use 7.1 oz of BCS-AA10717 20 WSP Herbicide per A. Do not exceed 7.1 oz per A in a contiguous 12 months.

o In the Non-selective Non-Crop Uses sect ion, we recommend that reference to “other hardscapes” be removed, or explicitly defined.

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### o Label language on spray drift management for broadcast ground applications would reduce potential exposur e to terrestrial and aquati c plants from off-field spray drift deposition. For consistenc y, we recommend inserting the identical language as provided for Esplanade 200 SC, Indaziflam 200 SC, and Indaziflam 500 SC formulations.
Table 1. Ecological Effects Studies for Indaziflam

Guideline MRID Study Title Issues Study Classification
850.1010 47443226 Indaziflam - Acute Toxicity to Daphnia magna in a 48 Hour Static Test Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1035 47443227 Indaziflam Techni cal - 96-hr Static Acute Toxicity Test with the Saltwater Mysid (Americamysis bahia) None Acceptable

850.1025 47443228 Indaziflam Technical - 96-hr Shell Deposition Test with the Eastern Oyster (Crassostrea virginica) under Flow-through Conditions Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1075 47443229 Indaziflam Technical - Acute Toxicity Study on the Fathead Minnow (Pimephales promelas) in a Static System over 96 hours Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1075 47443230 Fluoroethyldiaminotriazine - Acute Toxicity Study on the Fathead Minnow (Pimephales promelas) in a Static System Over 96 Hours None Acceptable

850.1075 47443231 Indaziflam-carboxylic Acid - Acute Toxicity Study on the Fathead Minnow (Pimephales promelas) in a Static System Over 96 Hours None Acceptable

850.1075 47443232 Indaziflam Technical – 96-h Acute Toxicity Study on Sheepshead Minnow (Cyprinodon variegates) under Static Conditions Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1075 47443233 Indaziflam Technical - A 96-Hour Static Acute Toxicity Test with the Bluegill Sunfish (Lepomis macrochirus) Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1075 47443234 Indaziflam Technical - Acute Toxicity Study on the Rainbow Trout (Oncorhynchus mykiss) in a Static System Over 96 Hours Test media was not centrifuged to determine dissolved test substance concentration. Supplemental



### Page 4 of 12850.1300 47443235 Indaziflam Technical – 21-day ChronicToxicity to Daphnia magna under Staticrenewal Conditions Effects to offspring were not measured & test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1400 47443236 Indaziflam Technical – 35-day Early Life Stage Toxicity test on the Fathead Minnow (Pimephales promelas) under Flow-through Conditions Statistically significant difference between negative and solvent controls for mean dry weight & test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1735 47443238 Indaziflam Technical – 10-day Acute Whole Sediment Toxicity Study with Freshwater Midge (Chironomus tetans) Overlying water concentrations were not centrifugedto determine dissolved test substance concentration Supplemental

850.1740 47443239 Indaziflam Technical – 10-day Acute Whole Sediment Test with Marine Amphipod Leptocheirus plumulosus under Static Conditions Overlying water concentrations were not centrifuged to determine dissolved test substance concentration Supplemental

850.2100 47443240 Indaziflam Technical – Acute Toxicity in the Bobwhite Quail (Colinus virginiamus) After Single Oral Administration (LD50) None Acceptable

850.2200 47443241 Indaziflam Technical – Subacute Dietary LC50 with Northern Bobwhite Quail (Colinus virginiamus) None Acceptable

850.2200 47443242 Indaziflam Technical – Subacute Dietary LC50 with Mallard Duck (Anas platyrhnchos) None Acceptable

850.2300 47443243 Indaziflam Technical – One Generation Reproduction Study on the Bobwhite Quail (Colinus virginiamus) by Administration in the Diet None Acceptable

850.2300 47443244 Indaziflam Technical – One Generation Reproduction Study on the Mallard Duck (Anas platyrhnchos) by Administration in the Diet Non-definitive NOAEC Supplemental

850.3020 47443245 Indaziflam Technical - Acute Contact Toxicity Study with the Honey Bee None Acceptable



### Page 5 of 12850.4225 47443246 BCS-AA10717 20WSP - Toxicity Test to Determine the Effects of the Test Substance on Seedling Emergence of Terrestrial Plant Species None Acceptable

850.4225 47443247 Indaziflam 500 SC - Toxicity Test to Determine the Effects of the Test Substance on Seedling Emergence of Terrestrial Plant Species None Acceptable

850.4250 47443248 BCS-AA10717 20WSP - Toxicity Test to Determine the Effects of the Test Substance on Vegetative Vigor of Terrestrial Plant Species An associated NOAEC/EC 05 could not be determined for the lowest EC 50 Supplemental

850.4250 47443249 BCS-AA10717 20WSP - Toxicity Test to Determine the Effects of the Test Substance on Vegetative Vigor of Terrestrial Plant Species Study failed to define a NOAEC or EC05 corresponding to the lowest EC25 for dicots. Supplemental

850.4400 47443250 Indaziflam Technical – Tier II 7-day Aquatic Plant Test on the Growth of Lemna gibba None Acceptable

850.4400 47443251 Triazine-Indanone – Tier II 7-Day Toxicity Test with Duckweed (Lemna gibba G3) None Acceptable

850.4400 47443252 Fluoroethyldiaminotriazine – Tier II 7-Day Toxicity Test with Duckweed (Lemna gibba G3) Failed to determine most sensitive endpoint Supplemental

850.4400 47443253 Indaziflam-carboxylic Acid – Tier II 7-Day Toxicity Test with Duckweed (Lemna gibba G3) None Acceptable

850.4400 47443254 Indaziflam-hydroxyethyl – Tier II 7-Day Toxicity Test with Duckweed (Lemna gibba G3) None Acceptable

850.4400 47443255 Indaziflam-olefine – Tier II 7-Day Toxicity Test with Duckweed (Lemna gibba G3) None Acceptable

Nonguideline 47443256 Indaziflam Technical – Growth Inhibition Test in a Water/Sediment System using Spiked Water with Duckweed (Lemna gibba) under Static Conditions Non-guideline Supplemental

850.4450 47443257 BCS-AA10717 SC 500 G/L – Tier III Ecological Effects Test in Outdoor Experimental Ponds Inhabited with Macrophytes Multiple deviations from guideline; was submitted as supplemental data Supplemental

Nonguideline 47443258 Indaziflam Tec hnical – Non-guideline Screening Test on Effects to Aquatic Macrophytes in Outdoor Simulated Ponds Non-guideline Supplemental

Nonguideline 47443259 Analysis of AE 1170437 concentrations in sediment samples of ALTERRA Study No. ALT.SC.2007.1 Non-guideline Extraneous Data - No study classification given.Nonguideline 47443260 Analysis of AE 1170437 concentrations in water samples of ALTERRA Study No. ALT.SC.2007.1 Non-guideline Extraneous Data - No study classification given.



### Page 6 of 12850.5400 47443261 Indaziflam Technical – 96-hr Test on the Growth of the Green Alga Pseudokirchneriella subcapitata None Acceptable

850.5400 47443262 Fluoroethyldiaminotriazine - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours Supplemental

850.5400 47443263 Indaziflam - carboxylic Acid - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours Supplemental

850.5400 47443264 Indaziflam - hydroxyethyl - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours Supplemental

850.5400 47443265 Indaziflam - olefine - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours Supplemental

850.5400 47443266 Indaziflam Technical - 96-Hour Toxicity Test with the Freshwater Alga (Navicula pelliculosa) Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.5400 47443267 Indaziflam Technical - 96-Hour Toxicity Test with the Saltwater Diatom (Skeletonema costatum) None Acceptable

850.5400 47443268 Indaziflam Technical - 96-Hour Toxicity Test with the Freshwater Cy anobacteria (Anabaena flos-aquae) Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

Nonguideline 47443269 Indaziflam Technical – Acute Toxicity Study on Earthworms (Eisenia fetida andrei) A 14-day test instead of a 28-day test was conducted. Supplemental

850.1010 47743303 Indaziflam 500 SC – Acute toxicity to Daphnia magna in a 48 Hour Static Test Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1010 47743304 Indaziflam 200 SC – Acute toxicity to Daphnia magna in a 48 Hour Static Test Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.1075 47743305 Indaziflam 500 SC – Acute toxicity to Bluegill Sunfish (Lepomis macrochirus) over 96 hrs Test media was not centrifuged to determine dissolved test substance concentration. Supplemental

850.2100 47743306 Indaziflam Technical – An Acute Oral Toxicity Study with the Zebra Finch None Acceptable



### Page 7 of 12850.3020 47743307 Indaziflam 500 SC – Acute Toxicity Study to the honeybee (Apic melifera L.) under laboratory conditions None Acceptable

850.4400 47743308 Indaziflam 500 SC – Tier II 7-day Aquatic Plant Test on the Growth of Lemna gibba None Acceptable

850.5400 47743309 Indaziflam Techni cal - 96-hr Test on the Growth of the Green Alga Pseudokirchneriella subcapitata None Acceteptable

850.5400 47743310 Indaziflam 500 SC - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours Supplemental

850.5400 47743311 Indaziflam 200 SC - 72-Hour Toxicity Test with the Freshwater Green Alga (Pseudokirchneriella subcapitata) Study length 72 hours; light intensities two times recommended levels Supplemental

Nonguideline 47743312 Fluoroethyldiaminotriazine - Acute Toxicity Study on Earthworms (Eisenia fetida andrei) A 14-day test instead of a 28-day test was conducted Supplemental

Nonguideline 47743313 Triazine-indanone - Acute Toxicity Study on Earthworms (Eisenia fetida andrei) A 14-day test instead of a 28-day test was conducted Supplemental

Nonguideline 47743314 Indaziflam – carboxylic acid - Acute Toxicity Study on Earthworms (Eisenia fetida andrei) A 14-day test instead of a 28-day test was conducted Supplemental

Nonguideline 47743315 Indaziflam 500 SC - Acute Toxicity Study on Earthworms (Eisenia fetida andrei) A 14-day test instead of a 28-day test was conducted Supplemental

860.6200 47743316 Indaziflam 500 SC – Survival, Growth, and Reproduction toxicity test on Earthworms (Eisenia fetida andrei) Did not test concentrations to guideline limit to dervive an LC 50 Supplemental



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### Table 2. Environmental Fate Studies for Indaziflam

Guideline Study Title MRID Classification Comments Are data adequate for Risk Assessment? Current Additional Data Need

835.2120 Hydrolysis 47443207 Acceptable N o significant issues affecting the
a cceptability of the study were noted. Yes None

835.2240 Photodegradation in Water 47443208 Supplemental Study duration not sufficient. C oncentrations of the 2 major t ransformation products were still i ncreasing at the study termination, p recluding the determination of the p atterns of formation and decline for
e ach. Yes None

835.2410 Photodegradation on Soil 47443209 Supplemental Study duration not sufficient.

T here was a decline in the dark controls (11%), material balances are
a cceptable. No explainable reason for d ecline in dark controls (e.g., stable to h ydrolysis) Yes None

47443210 Supplemental A pplication rate wa s 4x the maximum p roposed application rate to achieve
a ppropriate sensitivity. Kinetics may
n ot be accurately represented at the h igher application mass.

O verall recoveries of C14 residues f rom decreased during the study d uration.

A uthors did not demonstrate that
v olatile trapping method was efficient
a t trapping high concentrations of
v olatile gases (e.g., CO2) Yes None

47443211 Supplemental A pplication rate wa s 4x the maximum p roposed application rate to achieve
a ppropriate sensitivity. Kinetics may
n ot be accurately represented at the h igher application mass.

I n the California sandy loam, i ncreasing % of AR for diaminotriazine
w as observed at the termination of the stu d y precluding the determination of t he patterns of form ation and decline. Yes None. 835.4100 Aerobic Soil Metabolism

47443212 Supplemental Study duration not sufficient. This may
n ot be sufficient to accurately establish t he pattern of decline of the major t ransformation products.

R eplicates were not collected for three
o f the four soils tested, except for time 0

.
M oisture content was higher than
r ecommended in study guidelines (55%
o f max holding capacity vs 75% of 1/3 b ar soil moisture content) Yes None



### Page 9 of 12Are data Current adequate for Guideline Study Title MRID Classification Comments Additional Data Risk Need Assessment?

47443213 Supplemental Stu d y duration not sufficient. This may
n ot be sufficient to accurately establish t he pattern of decline of the major t ransformation products.

R eplicates were not collected for three
o f the four soils tested, except for time 0

.
M oisture content was higher than
r ecommended in study guideline (55%
o f max holding capacity vs 75% of 1/3 b ar soil moisture content) Yes None

47443214 Supplemental Study was conducted using d iaminotraizine (a degradate) as the starting material
Study duration not sufficient. This may
n ot be sufficient to accurately establish t he pattern of decline of the major t ransformation products.

M oisture content was higher than
r ecommended in study guideline (55%
o f max holding capacity vs 75% of 1/3 b ar) Yes None

47443215 Supplemental A comparison of the behavior of the t wo active isomers. Samples were
a nalyzed only for the parent
c ompounds.

T his study does not provide q uantitative data for the risk
a ssessment, it shows the behavior of t he two active isomers (diastereomers)
o f indaziflam (BCS AA10717). Used only for qualitative purposes. None

835.4200 Anaerobic Soil Metabolism 47443216 Acceptable M oisture content during the aerobic p hase was higher than recommended in study guidelines (55% of max holding
c apacity vs 75% of 1/3 bar) Yes None

835.4300 Aerobic Aquatic Metabolism 47443217 Supplemental Study duration not sufficient. Duration
n ot be sufficient to accurately establish t he pattern of decline of the major t ransformation products. Yes None

47443218 Acceptable Study conducted on Indane labeled
c ompound. Yes None 835.4400 Anaerobic Aquatic Metabolism 47443219 Acceptable Study conducted on Triazine labeled
c ompound. Yes None

47443203 Acceptable N o significant issues affecting the
a cceptability of the study were noted. Yes None 835.1230 Mobility - Adsorption / Desorption 47443204 Supplemental T he test compound was triazinei ndanone a transformation product of A E 1170437. Yes None



### Page 10 of 12Are data Current adequate for Guideline Study Title MRID Classification Comments Additional Data Risk Need Assessment?

47443205 Supplemental T he test compound wa s diaminotriazin e a transformation product of AE 1170437. Yes None

47443206 Supplemental T he test compound was AE 1170437-
c arboxylic acid a transformation p roduct of AE 1170437. Yes None

47443220 Supplemental Study conducted on CA Porterville sandy loam cropped with turf.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

47443221 Supplemental Study conducted on FL Monticello l oamy sand cropped with turf.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

47443222 Supplemental Study conducted on NC Wayne County l oamy sand cropped with turf.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

47443223 Supplemental Study conducted on CA Porterville sandy loam, bare soil.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

47443224 Supplemental Study conducted on FL Jefferson C ounty sand/loamy sand, bare soil.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

47443225 Supplemental Study conducted on NC Wayne County l oamy sand, bare soil.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None 835.6100 Terrestrial Field Dissipation

47743301 Supplemental Study conducted on Quincy loamy
san d , bare soil, in E phrata, Washington.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen sto r age. Yes None



### Page 11 of 12Are data Current adequate for Guideline Study Title MRID Classification Comments Additional Data Risk Need Assessment?

47743302 Supplemental Study was conducted on Oakville l oamy sand, bare soil, in North Rose, N ew York.
Storage stability st udy showed slow d egradation of degradate over the p eriod of frozen storage. Yes None

850.1730 Fish Accumulation 47443237 Acceptable N o significant issues affecting the
a cceptability of the study were noted. Yes None

47443279 Supplemental Samples fortified with olefin degraded slowly, (corrected mean recoveries 65- 88% following 427-433 days).
Samples were not stored for a sufficient d uration. N/A None

860.1380 Storage stability

47743328 Supplemental Study upgrades MRID 47443279;
c onducted for sufficient duration. Samples fortified with olefin degraded slowly, mean corrected recoveries
r anging from 65 to 88% following 427 t o 433 days and from 47 to 67% f ollowing 732 to 736 days of storage N/A None

Non-guideline Supplemental Information on Foreign Soils 47793401 Supplemental C omparison of foreign (German) soils t o location and soil taxonomy of US soil series. Yes None



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