UNITED STATES ENVIRONMENTAL PROTEC TION AGE NCY WAS HINGTON D . C .• 20460 

### DEC 09 2 0 10 OFFIC E OF C HEMICAL SAFETY A ND POLLUT ION PREV ENTIO N 

### MEMORAND UM S UBJE CT : 

### B E AD C he mical Profile for R egi strati on R eview : G amma-cyhalothri n

J ihad Al sadek 

## J v t.-...(' If" S c ience In format io n & An aly sis B ranch 

### F ROM: 

### N i kh il Mallampa lli , 

### E n

to

mo logist B io logica l A naly sis Branch Eliz abeth Hill , Ec o n omi s t E

c o n omic A na ly s i s Branch 

# /,U;/ /1-/1/1- 0 1 0 

# r:>**AJ...~**

T HR U :



### Diann S ims, C hief

## J:&.l-**"-,....~9--""- ,,/**  Sc ience In f ormati on and A nal ys i s Bran ch B io l ogical and E conomic Anal ysis Div isio n (7 503 P) TO : W ilhelmina L ivingston Chemical Revie w Man age r Pesti cide Reev a luat ion Di v i s io n (75 08 P) P eer R eview Pan el da te: M ay 12,201 0

Page 1 of6Intr oductio n Gamma- cyhalothrin i s in the clas s o f chemi stry known as syntheti c pyrethroids. T heir mode of action , acc ording to the In s ecticide Re sistance Action C ommittee (IRA C), i s to act as s odium channel modulator s that re sult in n eurotoxicity in the target insects . Pyrethr oids are derived from th e chemical s tructure of pyrethrum, a chemical produc ed by chry santhemum plant s. Gamma- cyhalothrin i s a restricted-use, br oad-spectrum , in secticide reg istered in the U . S. for mo st major aph id, caterpillar and beetle pe sts o n a w ide v ariety o f c rops and non-a gri cultural u ses. "G amma-cyhalothrin i s a mirr or i somer of lambda-cyhal othrin , the active in gredient in " Warrior®" brand in secticide. The gamm a i somer is reported to be approximately twice a s potent as the lambda isomer . There fore, gamma-c yhalothrin i s formulat ed w ith half the amount o f ac tive ingr edient and appli ed at s imilar rate s per ac re as W arrior®" ( Boucher 20 06). Thi s do cument f ollows a format re cently d eveloped b y B EAD to co nvey u sage inf ormation on p esticides that are beginning to un dergo regi stration review . The anti cipated audien ce for thi s paper c onsists of the team o f EPA s taff curr ently e valuating the regi stration s tatus o f gammacyh alothrin, and ev entuall y th e g eneral publ ic. Thi s document build s upon the d ata already provided in the "Usag e a nd Label Us e Data Packages" that are al so pro vided to Re gi stration Re view team s b y BE AD. 

### PRI MARY US E SITE S' G amma-cyhalothrin i s regi stered on a wide ran ge o f crops (und er th e brand nam es Co balt® and Pro axis®, am ong other s) a s w ell as for the treatment o f vari ous non-agricultural s ettings (eatin g e stablishm ents, feed mill s, anim al kennel s, etc .). It a lso has a f ew l abels for u se as a p ostharvest tre atment for almond s, cherrie s, ne ctarines, and pea ches. C rops f or which it i s r egistered include tree fruit , vege tables, and ro w and fi eld crop s such as alfalfa , ri ce, s oybean, and w heat. T he maj or u se s ites appear to be al falfa, s oybean, and w inter w heat (se e below f or further di scussion of these and o ther crop s). 

### C OMM ON FORMULA TIONS AN D A PPL ICATIO N METHODS ' Fonnul ations Formulations include the f ollowing: m icroencapsulated , liquid , emul sifiable concentrate, readyto-use, impre gnated c ollar-tag, pre s surized liquid , and granular. Application Method s G amma-cyhalothrin product s are ap plied a s crack and crevice and/or s pot treatment , indo or general s urface treatment, indo or premi se treatment , void treatment , c ontact and /or s urface tr eatment , s pray, dire cted s pray , perimeter tr eatment, broad cast, chemigation , high v olume s pray 1 P lease ref er to th e L UIS report f or a c omprehensive li st. 

### Page2 of6( dilute), lo w v olume s pray (co ncentrate ), o utdoor tre atment , o utdoor prem i s e tre atment , an imal treatment (po ur-on), anim al tre atment ( e ar tag), mound dr ench, so il tre atme nt (T ebanding }, soil in -furr ow treatment, c onservation tilla ge , m ound tre atmen t , band treatment , dip tre atment , and bark treatme nt. GAMMA · CYHA LOTHRIN U SAGE Agric ultural Us age Based o n p rivate ma rket pe s ti cide us age data f ro m 2004· 2008, the annua l tota l ag ricultural u sage o f gamma-c yhalothrin average d approximate ly 6, 000 pound s o f ac tive in gred ient for 6 00,000 ac re s ( GtK Kynetec , EP A p roprietary d ata, 2 004 -2 008) . It i s typ ically use d at very low r ates ( 0 . 0 1- 0 . 02 lb s a . iJ A) . G arnma-cyhalothrin w as fir s t re gistered Ma rch 3 1, 2 004 ( O PP IN) and according to o ur usag e d ata fro m 20 04-2008 , u sage h as been s te ad i l y i ncreasing . O ver the p ast five y ears , u sage h as s ignificantly incre ased for al falfa, soy beans . and winter w heat . • From 200 4-2 008. the l argest market s in term s of tota l pound s of active in gredient applied were s oybeans ( 51 % ) , a lfalfa (14 %), ric e (8%) , wi nter w heat (7 %), app le s (5 %), and co tt on ( 4%) (GtK Kynetec, EPA propr ietary d ata , 200 4.2008). T hese are a lso the large s t market s in term s of acres trea ted .

Pound s A I

S1 .. • S o )be ans • A lfalfa o Rice o Whe a t, Winte r • A p ple s • Cotton 

### • 0 '10,

,,

Ae r nTr nted 1 , 800. 000 .-- --- - - - -- ----,

200 4 2 005 2006 2007 2006 V

ear . Co llOn 

# .- O Rice 0

_ _ 

# . ... .. • So )Oe &n S

P age 3 0 f 6• A ccording to t he 2010 SLUA, the c rops w ith the h ighe s t percent of c rop tre ated we re apples and o nion s. App le s had an average and maximum perc e nt crop treated o f 5%, w hile o nion s had an ave rag e o f les s than 2.5% crop treated and a maxim um of 5% crop treated. Pl e a se refer to th e Sc reening L e vel Us age Ana ly s i s (S LUA) for a co mplete li st ing of crop P CT va lues . • T he s tates wi th t he mo st agr icultural u sage i n te rm s o f "po unds a i applied " are M innesota , Sou th D akota, Mis s i ss ippi, Iowa, Co lorado, an d New York. T his o rder s li g htl y d if fer s i n co mpari so n to ag ricultural u sage in term s of " acres tr eated ", as s een be low . P ounds AI

• M INN ESOTA • SOUTH DA KOTA o M ISSISSIPPI n IO WA • COLORADO a N EW YORK • Other

• MI NNESOTA

. IOVIIA OSOUTH DAKOT A OC Ol ORADO

. T EXAS

. N E W YORK 1 , 600 , 000

2004 2005 2006 2 007 2008 Year

N o n- Agricu ltur al Us age BEAD reviewed ava ilable non-agricultural s ources but did not fi nd any i nformation o n u se of gamma-cyhalothrin i n or o n n on-agri cultural use s ites . U SE TR ENDS Fro m 2 004-2008 , th e l argest m arket s in terms o f tota l pou nd s o f active ingredient applied we re s oyb e ans, alfalfa, ri ce , w i nte r w heat, app les , and c otton. T he u sage data f or all of the c rop s li ste d above we re exa min ed for trends . Pou nd s of gam ma-cyhalothrin u s ed on soybe ans , alfalfa , an d Page 4 o f6w inte r wheat i ncreased substantially since r egistration, whe reas pounds of g amma-cyhalothrin overall used o n rice , cotton, and ap ples fluctuated ove r the same period . See graph be low .

Gemma Cyh alothrtn Use Trend : Top 6 Crops 1 6 . 000 00 ..- - -_ - -- - - - -, ;; 

## • 1! 

## ,**.oo l---'** **=~** 20 04 2005 2006 2.007 2006 ' CAPPI es 

## 1

_

Q:l tton ;O R ce (]WnterWheat 

### , : P falfa Scybea ...

According to B EAD 's Offic ial Records Database, and RO 's Sec tion 1 8 database, t here have been no emergency exemption requests for gamma-cyhalothrin . The re are also no formal benefits asse s sment memoranda from BEAD for this insecticide. Gamma-cy halothri n is o ne of th e re commended con trol o ption s fo r a set of s ign ifican t pe sts i n t he c rops wi th the hi ghest u sage. In soybe an s, i t is re commended f or co ntrol o f s oybean aphid, Aphis g/ycines . This in sec t , i ntroduced fro m C hina, w as fir st detected i n th e U . S. in 2000 , and now oc curs throughout th e co unt ry's ma in soy bean produ ction regions. In a ddition to cau sing y ie l d losses in high inf estations, thi s aphid c an also tran smit se veral plant v iru ses ( Rice e t al . , 2 007) . While th ere are s everal o ther pyrethro id s, as we ll as neonicotinoids and organop hosphate s, me ntioned i n soybean aphid management recommendation s fro m m ajor p roduction state s ( e . g., Iowa, Wi sco nsin), garnma-cyhalothrin use in this crop may have increased in recent years as concern about th i s pest has grown among s oybean farmers . In alfalfa, gamma -cyhalothrin is o ne of th e rec omm ended o ption s fo r co ntrol of th e a lfalfa weev il , H ypera p astica . There are several o ther py rethroids a nd o rganopho sp hate s reco mmended f or th i s pes t as w ell. In So uth D akota, o ne of th e s tates with h igh g amma-cyhalothrin us age , gr asshoppers of v arious s pecies may al so be a t arge t o f py r ethroid tr eatment s (US DA 2 001). In wint er wh eat , major tar get p ests for gamm a -c yha l othrin appe ar to b e the Rus s ian w heat aph id (Diuraph is n oxia) and gree n bug, Schi zaphis grami num Ro ndani. The Ru s sian wheat aphid i s an other introd u ced inv a s ive pe s t that is capa ble o f p lant di sease transmi ss ion . Page 5 o f 6It is w orth not ing th at p yrethroid per f orman ce i s enhan ced in " cool temperatures " (Ri ce et a l. 2 007). S ince the majo r u se o f ga mma-cyhalothrin o ccurs in Mi dwestern s tates that ge nerally have co oler s p rin gs an d f alls , thi s as pect m ay b e ano ther f actor in th e po pularity o f thi s in secticide i n al falfa, s oybean, and wi nter wh eat. 

### Da ta n eeds re levant to BEAD's fut ure w ork on gamma -cyhalot hr in O btaining a dditional inf ormation on th e f ollowing it ems w ould i mprove BEAD's assess ment of th e importance of g amma-cyhalothrin as a pe st m anagement to ol. This asses s ment i s likel y to b e r equired as p art of th e r egistration rev iew of thi s pe sticide. l . Fo r non-agr icultur al an d p ost-harvest co mmodity u ses, inf ormati on on target pe sts, quantit y u sed, p ercent cr op treated ( or an e quivalent measure) , and treatment cos ts. 2. C o nfirm a ti o n of th e m ajor targ et p ests f or w hich g amma-cyhalothrin i s u sed i n ag ricultural pr oduction. 3. Resistance report s f or g amma-cyhalothrin in p opulat ions of imp ortant tar get pe sts. 4 . For ag ricultural u se s , wo rker act ivities that occ ur in tre ated field s at th e typical tim e of g amma-cyhalothrin ap plications. 

### REFERENCES Bou cher , J . 2 006. N ew V egetable C rop In secticide lMiticid elMolluscides . O nline art icle f rom th e U nivers ity o f Co nnecticut Coo perative Ex tension Sys tem. Av ailable at : http :/ /\'.iV<i'W.hort .uconn .ed wipm/ veglhtms /2006 insecticid. htm . G fK K ynetec , E PA proprietary d ata , 20 04-2008 Rice, M., M. O 'Ne al, and P. Pedersen. 2 007 . Soybe an A phids in Iowa - 20 07 . P ublication SP 247 o f th e Iowa S tate University Ex tension Service . Avai lable at ex tension .agro n.iastate.edulsoy bean/doc ument s/SP2 4 7A phids07 . pd f USDA. 2 001. C rop Profil e f or A lfalfa and Other Hay Pr oduction I n So uth Da kota . Ava ilable at: http: //\'.iV<iw .ipmcenter s.org /cropprofiles /CP fonn.cfrn .

Page 6 o f 6