UN I TED STATES ENV I RO N MENTAL PROTE C T I O N AGE NC Y WASH I NGTO N D.C. , 20.t60
OFF I CE O F CHEMICAL SA F ETY A N D POL LUTI O N PREV E NTION 

### PC Code: 047802 MEMO R ANDUM 

### March 28,20 1 6

S ubj ect : Addendum M emo randum Clarifying the Preliminary Env ironmental Fate and Ecological Risk Assess ment Co nclu s io ns for the Registration Review of Propoxur

To:



### Fro m :

T h ro u g h: 

### D P Barco d e No.: 432548 Brittany Pru itt , C hemi ca l Rcv iev,, Manag e r A v iva Jak ob , T e am Leader Kelly Sherma n , Branch Chief Ri sk Mana geme nt and Implementation Branch HI Pe s t icide Re-E va luati o n Divi s i o n (750 P)

### rvJ_t:!_**..J..-<-4Lg'** 

## 3/ 3 

## o / CJ..- 0 I f:. 

### H annah Yingling, Biologist 

### __:f)vtfl v {) 

### Gabe Rothman , E nvi ro nmental Scient is t

## #~ 

# ;{ / / E n vi ronmental Risk Branch V**r~v-'-" -~**  

### ..::::> 

### .>D/ 

# b Env ironm en ta l Fate a n d Effects Division (7507 P)
Mah Shamim, Ph.D., Branc h Chief Environmental Risk Branch V Env ironmental Fate and Eff ec ts Division (7508 P) 

## 3/c36 jl 6

T hi s memorandum serves as an addendum clarifying risk co nclu s ions desc ri bed in th e Pre limin ary Environ me nt al Fate a nd Eco log ica l Ri s k Assessment for the Reg istration Review of Propoxu r from the En vi ronme ntal Fate and Effec ts Division (EFED) (DP Barcode Nos. 414136, dated A ugu st 6, 20 14). The ri sk assess ment identified a potential for adverse imp ac ts to listed f reshwater aquatic inverteb rates , and therefore provided a corresponding, "May Effect" determi nation. These results were prov ided in both the Exec utive Summa ry (Sect ion 1. 2), Table 1.1 , the Ri sk Description Section (Section 3.2. 1) , and Table 4.1 of the assessment. T he risk assessment identi tied th e high est pot ential for ri sk with curr e nt hand-held sprayer outdoo r s pot treatment in sect ic id e uses of p r opoxur. Given li mited info rmat ion on th e label s , a thresho ld ana lysis was conducted t o identify the a mount of produc t which would cause a concern to aquatic in verteb rates, whi c h was th e mo st se n s iti ve aquatic s peci es informed by guide lin e studi es s ubmitted by th e registrant. In the risk assessment, it was dete rmi ned that 2. 75 gallo ns of propoxur per use s ite per yea r (Ta ble 3.2) would cause potenti a l adverse impacts to li s t ed aq uatic invertebrates in waterbodies occurring nearby propoxur treatments. This threshold amount of propoxur was determined evaluating s tandard pesticide runoff scenarios w ith pesticide treatments usin g the PRZM/ EXAMS model , and refl ected sparse use wit h one app li cat io n to one p roperty subject to runoff occur rin g within a 1 0-hectare watershed. Such use is understood to reflect actual spot treatments of propoxur which is not used in an organized manner within communities. Nonetheless , th e ri sk assessment identified a potential fo r adverse effects fo r li s ted f reshwater invertebrates on an acute basis with th e th resho ld application amount of 2.75 gallons per year per property , and therefore provided a corresponding, " May Effec t ", determination , although acknowledging that is a very h i g h application for a spot treatment (Sect ion 3.2.1 )

. It s hould be not e d that EFE D provided a , "No Effects " determination for all other listed aquatic and terrestrial organis m s, and did not id entify risks to non-listed freshwater in vertebrates

. Furthermore , no risks of concern were identified with other regi s t e red products of p ropoxur u ses outdoors i ncluding bait s tation s, spray cans, and its impre g nat ed insectic id e tag and tape strip products.
Since the ri sk assess m e nt , ad ditional in fo rm at i on on propoxur spot treatm e nt s were prov ided by th e Biolo gical and Economic A nal ys is Division ( B EA D). BEAD estimates that outdoor spot treatments ofpro p oxur would not exceed one ga ll o n per property per year (BEAD Pro duct Review Pane l Document, dated Ma r ch 23, 20 16)

. The rationa le on p ropoxu r spot treatment u se in th e B EAD document provid es strong evidence that propoxur is not commonly used at quantities even nearly approaching 2. 75 ga llon s. Th e refore , EFE D pro v id es a definiti ve, "N o E ff ects" d ete rmin ation for fr es hwater aquatic invertebr ates in thi s risk assessme nt a dd e ndum clarifi cation m e morandum. This determ in ation supersedes th e, " May Effect " risk determination for listed freshwater aquatic invertebrates presented in the Executi ve Sununary (Section 1.2 ), T able 1.1 , th e Risk Description Sectio n (Sect ion 3.2. 1 ), and Tab le 4.1

. Pl ease address any questions to Gabe Rollm1an at (703) 347

- 80 II or 1 -fannah Yingling at (703) 347 -0 297.

2