UNXTED STrlTES E NMEN'TAI, PROTECTION ilGF,NGY WASHINGTOND.C.
CfFFlfE OF PREVEIUTIOl. PESTICIDES AND TOXIC SUDSTALCES

PC Code: 107901 DP Barcodes: D339605 Date: March 5,2008

DRINKING WATER ASSESSMENT 

## 1

SUBJECT: Revised DrinkingWater As essment for reregistration of triforine for use on ornamentals. 

# S

FROM: Keara Moore, Chemist Environmental Risk Bra Environmental Fate and THRU: Tom Bailey, Branch Chief Environmental Risk Branch 111 J Environmental Fate 

### and cts Division (7507P) TO: Christine Olinger, RRBI Health Effects Division

ivision (7508P)

Attached is the sessment for the reregistration eligibility decision for tri sed to remove Confidential Business ons or characterization ofpotential drinking nements are necessary, please contact Keara

# Drinking 

# W Assessment for the Reregistratio Decision for Triforine

[Original: 0ctbber 19,2007;D3396061

N,N'-

### [l,4-piperazine-diylbis(2~,2-triehloroethy~dene)] bis[formamide] CAS ~e~istr) Number: 

### 26644-46-2

Prepared by: Keara Moore, Chemist PC

Reviewed by: Jim Hetrick, PhD, Senior Scientist Code: 107901



### U. S. Environmental Protection Agency Offieof Pesticide Programs Environmental Fate and Effects Division Environmental Risk Branch 111 1200Pennsylvania Ave.,

### NW Mail Code 7507P Washington,DC 20460I. EXECUTIVE SUMMARY 

## I This document reports the Tier 1drinking ater exposure assessment for triforinel conducted to support the human health risk assessment f r the Reregistration EligibilityDecision (RED). 

# 1 Triforine is a fungicide and insecticideregi tered for outdoor residential use on ornamentals, primarily roses. It is applied as an aerosol pray or through hose-end or tank-type sprayers at a maximum application rate of0.46 lb a.i./A, with multiple applications allowed at 7-10 day intervals. 

# I

Triforine is moderatelypersistent in soil a half-life of one to several months and it degrades rapidlyin water through hydrolysis and with half-lives of several days. Transformationin soil leads primarily and carbon dioxide as end products, but laboratory studies show formation of in some environments at levels up unknown degradate, construed to be its hydrate4. No ofthe degradates and this assessment Based on triforine's use pattern and its fate properties, aquatic exposure at the scale of 

### a drinking water watershed is is intended for small-scale use by cans or in volumes of onepint to one quart, which can treat a the CaliforniaDepartment of Pesticide Regulation applicatorsis at rates of <0.05 lb any triforine that of chronic exposure.

11. PROBLEM FORMULATION 

### This is a Tier 

### I drinking water uses modeling to estimate the groundwater and surface water in drinking water source water (pretreatment) that are highly vulnerable. This initial tier provides estimated exposure

SeeAppendix B for structure.
4 B for structure.111. ANALYSIS I 

### A. use' Characterization I 

# ~ Triforine is registered for use on roses, flowers, shrubs, and shade trees. It is used to control black spot, and to kill aphids, mites, and other insects. Triforinehas three Rose & Floral Spray (0.1% a.i., Reg. No. 239-2467), applied spray can; and Ortho Rose Disease Control (6.5% Insect & Disease Control Formula I11 (3.25% a.i., Reg. diluted with water to 0.0021 lb a.i./gal for sprayers. All products are labeled for outdoor residential use only. Based on the assumptionthat 5 gallons of solution are applied per 1000

### ft2,the application rate is 0.01 1 lb a.i./1000 R2,equivalent to a.i./A. Given the individual, residential nature ofthe use, though, it is unlikely that large be treated. The largest available formulation contains 1 quart ofproduct, equivalent to of dilute solution,which would be sufficient to treat 0.3 A. Labels indicate that for 2 to 3 applicationsmay be needed, and for disease control, applications as disease conditions persist, with no maximum number specified. 7-10 days for most uses but can be applied to azaleas at 2-3 day that triforine products are generally used by gardeners who make enthusiasts who make multiple applications. AD) estimates that more than 100,000 ates. Additional local use data are

gulation, which compiles Pesticide Use

users 

## . The PUR reports that in 2005, 400 applicationsoftriforine totaling ed 10/10/2007). This is not a rs, which is not likely to be the ent oflarge areas at the

B. Environmental Fate and Laboratory fate studies show that is moderately persistent in soil and degrades rapidly in study found low sorption to moderately mobile
measurement of 

### In soil,degradation with a half-life on the scaleof although a quantitative half-life could not be and low recoveries (MRID 4238041 1; Triforine was found to transform through the DT,, in three soils was observedto be 7 to 28 4323 1903,Acceptable; MRID 4323 1904, was examined as well and In most cases,
degradates are available in Appendix B. A terrestrial field dissipation in which two apple orchards, in New York and California, were treated with each at rates of 0.75 lb a.i./A with seven day application intervals. This use would be expected for currently registered uses. In one site, triforine was a half-life of 133 days, while on the other site, the observed half-life was analyzed for the parent compound and so did not consider dissipation not adequate to determineif triforine leached to groundwater. Triforine may reach surfacewater through runoff, and/or erosion. In aquatic environments, it degrades rapidly through hydrolysis at (tlI2:2.9 to 3.1 d; 

### MRID 42647702) and through photolysis (dark corrected tlI2:4 42647701). No data for aquatic metabolism are available. The major degradates hydrolysis were WOS-2379 and an unidentified compound assumed to was formed at a maximum of approximately60% to approximately 15%by the end ofthe study; day 31. The of WOS-2379 reach approximately20% on day 1 1 day 3 1. No additional environmental fate data are

C. Drinking Water Exposure Modeling Based on the limited use pattern and oftriforine, exposurein drinking water is expected to be low. Tier 1 screening level estimated drinking water concentrations assumptions are required in modeling exposure orted EDWCs are expected to be overestimates, but the extent of overestimationcannot be The followingis a descriptionof the models used, the model inputparameters, and of the output from these simulations. 1. Models Screening level estimated drinking water c: ncentrations (EDWCs) oftriforine were generated 

# 9' using the Tier I models FIRST, for surface ater, and SCIGROW, for groundwater. Input parameters were selected based on laborato y fate data in accordance with EFED's input parameter guidance. Models, input parame er guidance, and additional information about the

.

# i

5models' assumptions and uncertainties are httn://ww\v.e~a. gav/n~19efed 1/~nodcls!wate SCIGROW (version 2.3; dated July 29,20( estimate pesticide concentrationsfound in 1 developedby regressing the results of Pros Index of Leaching Potential (RILP). The F soil-water partition coefficient. The output might be expected in shallow unconfined a FIRST (version 1.1.O; dated January 1,20C screeningtool to estimate pesticide concen FIRST is a single-eventmodel (onerunoff applications. FIRST is hardwired to repres by the Office of Pesticide Programs to asse on a real reservoir, ShipmanCity Lake in I contamination.The singlerunoff event mo reservoir. This amount can be reduced due to soil in the field. FIRST also uses a Perci within the watershed that is planted to the I was applied in this assessment because the] the entire watershed is planted with omamc to overly conservative risk estimates. 2. Modeling Approach andInput Pard Tables 1 and 2 summarizethe model input These parameters were selected in accorda 2002a). The maximum single application 1 given the manner in which triforineproduc of application rate in lbs a.i./A may not be number of applicationsis assumed to be tvr do not restrict use to a maximum number c throughout the season, so it is likely that sc Some minor uses also allow an application expectedto be minor given the conservativ the watershed with all users applyingon th Registrant-submitted data for triforine inch The aerobic soil metabolismmodeling inp~ bound on the mean (61.9 d) and for SCIGP partitioning coefficients, both models use 

### E non-sand value (36 rnl/&,), and SCIGROP no aerobic aquatic metabolism data availal: stable to aquatic metabolismwith hydrolys and the dark corrected photolysis half-life, railable at the EPA's water modeling website,
I)is a regression model used as a screening tool to ,oundwater used as drinkingwater. SCIGROWwas :ctive Ground Water studies against the Relative LP is function of aerobic soil metabolism and the )fSCIGROWrepresents the concentrations that lifers under sandy soils. ) is a metamodel ofPRZM and EXAMS used as a ations found in surface water used as drinking water. vent), but can account for spray drift from multiple nt the Index Reservoir, a standard water body used s drinkingwater exposure (OPP, 2002). It is based inois, that is known to be vulnerable to pesticide :s a maximum of 8% ofthe applied pesticide into the o degradation on the field and the effects ofbinding ~t

Cropped Area (PCA) factorto adjust for the area odeled crop. A PCA ofunity (themost protective) is no PCA for ornamental uses. This assumesthat ltals treated with triforine, an approach likely to lead

vleters arameter values used in FIRST and SCIGROW. :e with EFED's input parameter guidance (EFED, te of 0.46 lb a.i./A is used for modeling although, ; are applied, the traditional agricultural expression :presentativeoftypical use. For this assessment, the with an application interval of seven days. Labels applications and statethat applicationscan be made ieusers apply triforine more often than twice a year. nterval oftwo days. These uncertainties are initial assumption that triforine is used throughout same day. ie three measured aerobic soil metabolism half-lives. for FIRST is the upper 90th percentile confidence )W, the input is the mean (42.9 d). For soil-water

,c. Of five measured values, FIRST uses the lowest uses the median value (99 ml/a,). Because there are ;

and hydrolysis is rapid, triforine is assumed to be Ias the rate-determining aquatic process (t,,,: 3.I), d, is used.Application Rate (lb a.i./A) Number ofApplications 

# I Triforine Use Closure Memo (CaseNo. 2720). The label does not specifymaximum Current labels. number of applications,but two is assumed to be protective. Interval between Applications (days) Percent Cropped Area

I 1 Organic Carbon Partition Coefficient (KO,;mL/goc) Aerobic Soil Metabolism Half-life (days) Most protective. MRID: 42304101.

MRIDs: 43231903, 43231904.

Current labels. Product Chemistry Wetted in? Some minor uses allow a 2 day applicationinterval. 

## --- No PCA for ornamentals. Lowest non-sand value. (36, 88,99, 118, 122mL/goc) 90" percentile upper confidence bound on the mean (23.2,49.2,56.4d) Default. TriforineUse Closure Memo (CaseNo. 2720) Method of Application Ground spray Solubilityin Water @ 2ooc, unbuffered (mg/L or ppm) Aerobic Aquatic Metabolism Halflife (days) No data are available. Assumed that hydrolysis is the rate-determining aquatic process. Hydrolysis Half-life @ pH 7 (days) MRID: 

# 1 42647703. 

# I Single measured value. Aquatic Photolysis Half-life @ PH 7 (days)

Triforine Use Closure Memo Current label. 

# I (CaseNo. 2720) 

# I MRID: 

# 1) 42647701.

Maximum Application Rate (lb a.i./A) Number of Applications per Year Organic Carbon Partition Coefficient (K,; mL/goc) Single dark-control correctedvalue.

Aerobic Soil Metabolism Half-life (days) 2 99 Assumed. MRID: 42304101.

MRID: 42.9

# 1 1 4323 1903, 43231904. No maximum specified on label. Median value (36, 88,99, 118, 122mLIg,). 

## ---- Mean value (23.2,49.2,56.4 d).3. Modeling Results 

# I For surface water, the modeled EDWCs and annual average exposure are 85.1 ppb and 0.84 ppb, respectively. For and average exposure estimates are 0.43 ppb. Modeling output files in Appendix A. Surface water EDWCs arebased on FIRST and represent untreated surfacewater concentrations. The one-in-1 0-year peak is used for acute endpoints and the one-in-1 0-year annual average endpoints. Groundwater EDWCs arebased on that mightbe expected in shallow used forboth acute and chronic endpoints. The estimated concentrationsprovided in th s assessment are conservative estimates of concentrationsin drinking water. If dietary 'sks require refinement, higher tiered crop-specific 

# 1, and location-specificmodels and modeling gcenarios can be used. D. Monitoring Data 

## 1 Therewere no national-scale monitoring found for this assessment. This is based on a search ofthe U.S. Geological Service Water Quality Assessment database (NAWQA, 2007) and the USGSIEPA Reservoir Program (Blomquist et al., 2001). E. Drinking Water Treatment

IV. CHARACTERIZATION There is no available informationon water treatment effects on triforine.

The estimated concentrations were generated from Tier 1models and are conservative estimates of drinkingwater. Tier 1 modeling is based on sites and includes protective assumptions FIRST, the Tier 1 surface water model, agricultural fields and may not be A major uncertainty assumes that the entire watershed has been treated with triforine. Given the nature triforineuse, this is unlikely and so leads to overly protective EDWCs. Another the reported EDWCs are for the parent only and do not consider potential The rapid hydrolysis oftriforine limits its exposure in drinking exposure to the degradates.V. REFERENCES I I 

### .B. Birchfield. 200 1.
Sacramento, CA.

Environmental Fate and Effects Division.


### . Guidance for SelectingInput Parameters in U. S. Environmental

Environmental Fate and Effects Division. 2 05. FIRST (F)IFRA (1)ndex (R)eservoir (S)creening (T)ool. Tier 1Model for Drinki g Water Exposure: User's Manual. htt~://www.e~~a.novi~r)~efedl /models/wates 

# ." first users manuaf.htm NAWQA. 2007. USGS National Water Quality Geological Survey. Available at:,' 

### http://infotrek.er.usgs.gov/traverse/r!p=NA7NQA:HOME:37655 2007. Office of Pesticide Programs. 2000. Part A. Drinking Water Assessments. Assessment Data Warehouse. United States 1952889201 9. Accessed August,

Guidance for Use ofthe Index Reservoir in 

### httl~:ii.c7iww.e-~a.aov~o~pfeadl/trac/science/reservoir.~dfModeling and Outputs 

### FIRST V. 

### 1.1.0; January 

### 1,2007
RUN No. 1 FOR triforine 

# I ON ornamental * INPUT VALUES * -------_--_--______------------- ................................... RATE (#/AC) No.APPS & SOIL SOLUBIL APPL TYPE %CROPPED INCORP

ONE (MULT ) INTERVAL Koc (PPM ) (%DRIFT) AREA (IN)

~~~~~~~~~~~~~~~~~~~~------------ ___--_--___-__--------------------- .460( -885) 2 7 36.0 

# 1 28.0 GROUND( 6.4) 100.0 -0

METABOLIC DAYS UNTIL HYDROLYSI PHOTOLYSIS METABOLIC COMBINED

PEAK DAY (ACUTE ) CONCENTRATION CONCENTRATION 85.145 -835


### SCIGRO Wv.2.3; July 

### 29, 2003

Application Number of Total Use Koc Soil Aerobic rate (lb/acre) applications ( b/acre/yr) (ml/g) metabolism (days) SCIGROW

groundwater screening cond (ppb)

................................. FOR AQUATIC PESTICIDE SciGrow version 2.3 chemica1:triforine time is 10/11/2007 15: 4:11 EXPOSUREAPPENQIX B: Structures

N-[piperazine-1 -yl-(trichloromethy1)methyl ne] forrnamide hydrochloride 

# r

piperazine x HClHydrate of WOS-2379 

### 1 1

-(1-formamido-2,2,2-trich1oro)-ethyl-4-(2, 

### - dihydroxy-1 -oxo-ethyl)-piperazine 

# 2