### UNITED STATES ENVIRONMENTAL PROTECTION AGENC Y WASHINGTON , 

### D.C
. 20460 O F FICE O F CHE MI CA L SAFETY A N D P OL LU TIO N P REV E N TI ON


### MEMORAN DUM DA T E: A u g u s t 12 , 2 01 5 SU BJE C T: B i fe n azate . D raft Hum an Healt h R i s k As sess ment in Support of Reg istration Review.



### F ROM : PC C od e : 000586 Dec is ion Nos.: 495937 P e tit ion Nos.: NA Ri s k Assess m e nt T y p e: Single Chemical/ Aggregate TXR N o . : NA MRID N o . : NA DP Ba r co d es : 0423 162 Reg is tra tio n No . : 7267

- 1 R eg ul a to ry Ac tio n: Registra t ion Review Case No.: 7609 CAS No.: 149877-41-8 40 C FR: 

### § 180.572 Monica Hawkins , Ph
. D., M.P.H
. , Environmenta l I l ealth S c ien t ist/Risk Assessor

# ~4-V Risk Assessment Branch VI

## '//~ Health Effects Divi s ion (7509P)**~** 

### THRO U GH : Donna S. Dav is. Acting Bran c h Chief 

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### ~ Risk Assessme n t Bra n ch VI 'fd:JIJVV-A...V 

## r Health Effects D iv ision (7509 P) and 

### V e-. , .. . h....-t...

- Lata Venkateshwara, ExpoSAC**Rev~e~** • t / • 1

· e;. Ivan Nieves, ExpoSAC Reviewer 

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- Exposure Science Advisory Committee (ExpoSAC) 

### I I-I E D


### T O : Garland Waleko. Chemical Re v iew Manager Cathryn Britton , Team Leader Kevin Costello , Branch Chief Pesticide Re-Evaluation Div ision (7505 P ) Risk Management 

### & Implementation Branch 3 ( RMI B 3) 

### 1.0 E xec u tiv e S um mary As part of Registrat io n Review, the Pestic ide-Re

- eva luation D i v is ion ( PRO) of OPP has requested that the H ealth Effects Di v ision (H E D ) conduct an occupational and resid e ntial ex posure assessment, as needed, to est imate the ri sk to h u man healt h th at wi ll res ult fro m the Page 1 of 4currently registered u ses of bif e nazate. H ED rece ntly conducte d a human health ri s k as sess ment for the active ingredient , bifenazate ( W. Wassell et al., 0 3 882 2 8 , 6/ 25 / 20 14). Since the previou s risk assessment , no changes were made to the hazard characterization and use profile ; therefore this docum e nt serve s as the d r aft ri sk asse ss m ent fo r bifenazatc for the purpo ses of regi s tration review. A total agg regated risk index (A RI ) was used since th e le ve l of concern va lues for dermal exposure (100) and inhalation exposure (30) are different. The target ARl is 1; th erefore ARls of le ss than 

### J res ult in risk estimates of concern. All ARls we re g reater than 1 and are not ri s ks of concern , except for the following sce narios that require sing le layer of g l oves: ( I ) mixin g/loading liquid s for aerial and chemigation applications and (2) mixing/loading / application of liquid s via mechanically press urized handgun (fo li ar). The most recent ri sk assessment did not include a spray drift exposure and ri s k assessment; therefore , a quantitative s pray -drift exposure/ risk assessment was conducted for bifenazate and is include d herein. Bife n azate is a selective miticide/ insectic ide that contro ls the motile s tage of mites either by direc t contact or throu g h contact with foliar residues. The reg iste red formulations for bif e nazate include wettable powders (WP) in water-soluble packe t s (WS P )
. so lubl e concentrates (SC), water
- di s per s ibl e g ranules (WDG), and flowable co nc entrates (F I C). The maximum application rate i s 0.75 lb ai / acre for use on timoth y forage and hay and 0.5 lb ai /acre for u se on pome fruit. Bifenazate is regi s tered for u s e on various agricultura l crops and on ornan1entals and non-bearing fruit crops ( citrns, berries , currants, dates , figs, a nd p e rs immon s)
. Dermal ri s k estimates were evaluated for ad ult s. D e rmal and incidental o ral risk estimates we re evaluated for chi ldren (1 to< 2 ye ars o ld ). The risk est imates from exposure to bifenazate related to s pray drift result in no risk s of concern at the fie ld edge for either groundboom, aerial applicat ions , or ai rbl ast orchard applications. 

### 2 . 0 No n - O cc up a tion a l Spray Drift Expo s ure a nd Ri s k Es tim ates Off-target mo ve ment of pesticides can occ ur via m any types of pathways and it i s gove rned by a variety of factors. Sprays that are re leased and do not deposit in th e appl ication are a e nd up offtarget and can lead to exposures to those it may direc tly contact. The y can also dep osi t o n surfac es where contact with res idue s can ev entuall y lead to indire ct exposure s (e. g., children playing on lawn s wh e re res idu es hav e deposite d next to treated field s). The potential ri sk est im a tes from these residues can b e calcu lated usin g drift modelin g onto 50 feet wide lawn s coupled with methods employed for residential risk assessments for turf products. The approach to be used fo r quantitatively incorporatin g s pray drift into ri sk a ssess ment is based on a premi se of compliant applications which , by definition , s hould not result in direct ex po s ure s to individuals becau se of existing label languag e and oth e r regu latory requirements intended to prevent th e m . 1 Direct exposures would include inhalation of the spray plume o r being sprayed direct ly . Rather. th e exposures addressed here are thou g ht to occu r indire ctl y through contact with impacted areas , s uch as res idential lawn s, when compliant applicati o ns are conducted
. Given thi s premise, expos ure s for children (1 to 2 yea rs o ld) and adults who have contact with turf where residues are assume d to have depo s ited v ia s pray drift thus re s ulting in an indirect

1 Thi s approac h is consist ent w ith th e requirements of the EPA 's Worker Prot ec ti o n Stand ard. Page 2 of 4

### exposure are the focus of thi s an a l ys i s analogous to how exposures to turf products are considered in ri s k a ssess ment. In 

### order to evaluate the drift pote ntial and associated ri s ks , an approach based on drift modeling co upl e d w ith t ec hnique s u se d to evaluate res idential u ses of pesticides was utili zed
. Essentially, a residential turf assessme nt based on exposure to depo s ited re s idue s has been completed to address drift from th e agricultural applications of bifen azate. ln th e spray drift scenario, the depo s ited residue valu e was d e te rmin e d ba se d on the amount of spray drift that may occur at vary ing distances from the edge of th e treated fi e ld usin g th e AgDrift (v2. l. 

### l) model and the 

### Res id ential Expos ur e Assessment Standard Operating Proc ed ur es Addend a 1 : Consideration of Spray Drift P ol i cy . Once the de p os ite d residue va lues were determined , the re mainder of the spray drift assessme nt was based on th e al go rithm s and input valu es specified in th e recently re v ised (20 12) 

### Stand ard Operating Procedures Fo r Res idential Risk Assessment (SO Ps )
. A sc re enin g approach wa s developed based on th e use of the AgDrift m o del in s itu atio n s where s p e cific label g uidanc e that defines application parameters is not available. 2.3 

### Ag Drift i s appropriate for u se only when application s are made by aircraft, airblast orchard sprayers , and g roundboom sp rayers. Wh e n AgDrift was developed , a series of sc reenin g va lu es (i.e
. , the Ti er 1 opt ion) were incorporated into the model and re present each equipment typ e and u se under v aried conditions
. The screening options spec ific ally r e commended in this me thodology were s elected becau se they are plausible and represe nt a rea so nabl e upp e r bound le ve l of drift for co mmon a pplication meth o ds in ag riculture . The se screening options are con s iste nt with how spray drift i s considered in a number of ecolog ical risk assessments and in the proc ess u sed to develop drinkin g water co ncentrations used for ri s k as sess m e nt. In all cases, eac h sc enar io is to be evaluated unless it is not plau s ible based on th e anticipated use pattern (e.g
.. herbicid es are not ty picall y applied to tree canopies) or speci fi c labe l prohibition s (e
. g. , aeria l app li catio n s ar e not allowed). Section 2 .1. I 

### provides the screen in g level drift related ri s k estimates. 

### 2.1.1 Ri s k Estimate s F rom Lawn Deposition A djacent to A pplication s The s pray drift risk estimates are based on an estimated dep os ited r es idu e concentrat ion as a re s ult of the sc ree ning l eve l agricultural application scenar ios. Bif e nazate is u sed on vario u s ag ricultura l crop s and can be applied via groundboom, aerial , and a irbla s t equipment. Bifen aza t e i s also regi s tered on orname ntal s and non-bearing fruit crops (ci tru s, berries , currants , da tes, figs , and per s immon s). The spray drift a ssess ment was conducted using the hi ghes t regi s tered application rate of 0. 75 lb a i / acre for use on tim o th y forage and hay for g round and aerial appli ca tion and 0.5 lb a i / acre for airblast appl icat ion. The re co mmended drift sce nario scre e ning level o ptions are 

### Iisted below:



### • Groundboom applications a r e based on the Ag Drift <l!> option for hi g h boom hei g ht and u s ing very fin e to fine spray t y pe u s in g th e 90 1h 

### percentile res ult s . 

### • Ae rial applications a re based o n th e use of AgDr ift® Tier I 

### aeria l option for a fine to m ed ium s pray type and a serie s of other parame t e rs , w hich w ill be de sc rib e d in mo re

2 http : //www.a g drift.com / 3 otc th at for man y case s th e s cen a r ios outlined in the s creenin g a pproa ch repre s ent actual u s e prac ti c e so risk ass e ssors shou ld be aw a re and charac terize thes e approp ri a tel y . Page 3 of 4detail below (e.g., wind vector as s umed to be I 0 mph in a downwind direction for entire app li cation/drift event). 

### • Orchard airblast applications are based on th e Ag Dri ft op tion for Sparse (Young/Dormant) tree canopies. D e rmal ri sk es timate s have been eva luated for adults. Dermal and incidental 

### oral risk estimates were eva lu ated for children (1 to < 2 yea rs old). Th e total app li cab l e LOC is I 00 so MOEs < 100 would be of concern . C hildren ' s ( 1 < 2 years o ld ) dermal and in c idental oral ri sk est im ates from exposure to bifenazatc related to sp ray drift result in no ri sks of concern at the fi e ld edge for either groundboom , aerial , or airblast applicati ons. Ad ult d er mal risk est imate s from expos ure to bifenazate relate d to spray drift r es ult in no risks of concern at the field edge for either gro und boom , ae ri al. or airb la s t ap pli cation s . Re s ult s are prese nted in Tables 2. 1. l. and 2. 1 .2. below.

Tab le 2.1.1. Adult Risk Estimates (MO Es) Re lated to Ind i r ect Ex posure to S pray Drift for Bife n azate fo r the Dermal Route of Exposure

Application S p ray T y p e / Ap plicati o n Est im ated TTR At Edge Nozzle Equipment Confo?.uration Rat e ( lb ai / A) ( u g/c m2) Dermal MOE Timoth y Forage and Hay A e rial Fin e to Medium 4.400 Ground boom Hi g lt B oom V e ry 0.75 0.0833625 6,100 fine to Fin e P ome Fruit Airblast Sp ar se 0.5 0.055575 12 , 000

T a ble 2
. 1.2
. C hi l dren ( I < 2 yea r s o ld) R is k Estimates (M O Es) Rel a ted to Indirect Exposure to Spray Drift for B i fenazate for Derma l and Incidenta l Ora l Route of Exposure At E dg e At Estimated E dge App l ication Spra y T y p e/ Nozz le Application TTR 1 Equipment Co nfi g uration Rate ( lb ai / A) ( u g/c m2) Der mal Incidental Oral MO E MOE Timothy Forage and Hay Aeria l Fine to Medium 2 ,200 3 10 Hi g lt B oo m Very 0
. 75 0.08336 25 Grou ndb oo m fine to Fine 3 , 100 420 Pome Fruit Airbl ast Sparse 0
. 5 0.055575 6 , 000 820 

### Note: Thi s m e m orandum was reviewed by the Exposu re Scie nce Advisory Comm i ttee (ExpoSAC) on July 23 , 20 15.

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