Docket Number EPA-HQ

-OPP-2012-0105 www .regul atio ns.gov



# METOFLUTHRIN Interim Registration Review Decision Case Number 7445 September 2014
Approved by:·

### ~ 

## P**>'J)** Richard P. Keigwin, Jr. Director Pesticide Re-evaluation Division

## Table of Contents

I. Introductio n ........... ... . ........... ... . .......... ............. ... . ....... . . ............. .. . ............ ................. ............. .. 3 A. Background

. . .......................................................................................... 5 II. Scientific Assessments ........................................ . .................................................................... 5 A. Human Health Assessment .................................................................................. . ... . ........... 5 Hazard Characterization and Ri sk ....................................................................................... 5 Dietary Exposure Assessment .............................................................. . .............................. 5 Food Tolerances
................... . ............................................................................................... 5 Re s idential and Occupational Exposure .............................................................................. 5 Human Incidents

. .. ...................................... ........... ............... . .. .. .. ..... .... . .............................. 6 B. Environmental Assessment ..................................................... . .. . ... . ..... . ........... .. .. .. .. .. ......... 6 Environmental Fate and Exposure ..................... . ..................... . .. . .. .. .. ... . .. ..... ................. .. .. .. 7 Ecological Risk Characterization

.. .. ........... . ... .......... ................... ......... .. .............................. 7 Ecolog ical Incidents ............................. ....... ·- ............................................8 Endangered Specie s Assessment ........................................................... . .......... 8 Endocrine Disruptor Screening Program ........................................................... .......... ........ 8 III. Interim Registration Review Decision ....................................... . .......................................... 9

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## I. Introduction This document is the Environmental Protection Agency's (EPA or the Agency) Interim Registration Review Decision for metofluthrin and i s being issued pursuant to 40 CFR sections 155.56 and 155.58. A registration review decision is the Agency's determination whether a pesticide meet s, or does not meet, the standard for registration in the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA). Further information on metofluthrin can be found in EPA's public docket (EPA-HQ-OPP-2012-0105) at www.regu l ation s .go v . FIFRA, as amended by the Food Quality Protection Act (FQPA) of 1 996 , mandated the continuous review of existing pesticides. All p esti c ides distributed or sold in the United States generally must be regi stered by the EPA based on sc ientific data showing th at they will not cause umeasonable risk s to human health or to th e enviro nment when used as directed on product l abe ling. The registration review program is intended to make sure that, as the ability to asses s and reduce risk evolves and as po li cies and practices change, all registered pes ti c ides continue to meet the statutory standard of no umeasonable adverse effects. Changes in sc ience, public policy, and pesticide use practices will occur over time. Through the registrat ion review program, the Agency periodically reevaluates pesticides to make sure that as these changes occur, products in the marketplace can continue to be used safely. Information on this program i s provided as www.epa.gov/opp s rrd l /registration r e view/

. In 2006, the Agency implemented the registration review program pursuant to FIFRA section 3(g) and will review each registered pesticide every 15 years to determine whether it conti nues to meet the FIFRA standard for registration. Pursuant to 40 CFR sect ion 155.50, EPA formally initiated reg i strat ion review for metofluthrin (case 7445). Th e fo llowing highlights signif icant events that have occurred during the registration review of metofluthrin:

• June 2013- Pub lication of Metofluthrin Preliminary Work Plan (PWP) for a 60-day public comment period. The PWP

**w~s** accompanied by Registration Review: Preliminary Ecological Risk Assessment and Endangered Species Effects Determination for Metofluthrin; Metofluthrin. Human Health Risk Assessment for the New Use to Control Bed Bugs and to Support Registration Review; Metofluthrin: Re view of Human In cidents; and the De Minimis Subgroup Opinion on Metofluthrin.

• December 2013- Final Work Plan (FWP) for metofluthrin was issued. Four public comments were received duri ng the 60-day comment period for the metofluthrin PWP. These comments did not result in changes to the work plan or schedu le; thus, the FWP did not modify the PWP.

o The FWP noted that no additional data were anticipated to be needed for the metoflu thri n registration revi ew because s ufficient information was available to conduct a risk assessment to support a propo sed regi stration review decis i on, pursuant to 40 CFR sect ion 155 .53(b).

3o The FWP noted that the Agency intended to revi si t the human inci dent data base for incidents associated with the u se of metofluthrin.


### o A Summary of Public Comments Received on the Preliminary Ecological Risk Assessment and Endangered Species Effects Determination Conducted for the Registration Review of Metofluthrin was posted to the docket along w ith the FWP.

• June 2014- The metofluthrin Pr oposed I nterim Registration Review Decision pub l ished in the Federal Register (79FR 32284) (FRL-9911- 16) for a 60 day comment period. Three comments were received during the comment period. T he Agency has also po sted for public comment the two document s that finalize the ecological and human health risk assessment s for metofluthrin: Response to Public Comments Received on the Preliminary Ecological Risk Assessment and Endangered Species Effects Determination Conducted for the Registration Review of Metofluthrin and Metofluthrin: Review of Human Incidentsfor Preliminary Risk Assessment. Comments received from the San Francisco Bay Regional Water Quality Control Board and the California Stormwater Quality Association (CASQA) were s imilar. The commenters expressed their belief that a full eco logical environmental assessment was needed , particularly for metofluthrin in urb an waters. Of particular concern to these organizations were the metofluthrin tab letop mister and bedbug u ses. The Agency believes that the low usage, the limited amount of metofluthrin that will transfer from the sk in or mattresses into washwater, and environmental fate characteristics of metofluthrin, particularly the s hort half-lif e of metofluthrin due to photolysis, result in very lo w potential for environmental exposures for all registered uses of metofluthrin. Given the low exposure potential, the Agency has concluded that additional toxicity data or a quantitative ecologica l assessment are not needed to make the ecologica l risk conclusions at thi s time. If the use pattern for metofluthrin is expanded or changes over time in a way that could result in high er exposure potential , the need for additional toxicity data will be revisited. A third comment from the Center for Biological Diversity indicated agreement with EPA's ESA approach and conclusio ns and required no subs tanti ve response.
• September 2014- The three comments received during the Proposed Interim Registration Decision did not change the data requirements or timeline for registration review, therefore, the Agency is now publishing and placing in the public docket its Interim Registration Review Decision for metofluthrin. Also being posted to the docket is the Agency's Response to Public Comments on the Preliminary Ecological Risk Assessment for Metofluthrin. The documents cited above an d additional information on metofluthrin can b e found in 

### EPA's public docket,

**EPA~HQ-OPP 2012-0105,**  

### accessed at www.regulations.gov

.

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### A. General Background M eto fluthrin is a Type 1 synthetic pyrethroid in se ct repe ll ent and in sec ticide. Th e first pe stici de produ ct co ntaining metofluthrin w a s regi stered in 2006 for u se in res idential and co mmerc ial ar e a s, including barn s, sta bl es, kennel s, p atio s, porches and camp s ites. M etofluthrin is formulated a s an impregnated material , press urized liquid and s olubl e concentrate. Metofluthrin is not regi stered for food u ses. There are a number of product s containing metofluthrin a s the sole active ingredi ent that are registered for use as repe ll ents for adult mo s quitoe s. The products regi st ere d for outdoor u se include an impr egnated paper strip , a battery-operated perso n al outdoor insect repellent fan , an impregnated fiber gl ass ring he ated b y a candle, and a battery-operated automated mi ster. The regi s tere d indoor use is a s olubl e co ncentrate used as a s pray to kill bedbugs. 

### II
. Scientific Assessments A. Human Health Assessment A su mmary of the A ge ncy's human health risk asse ss ment is presented below. The Agency use d the mo s t upd ated Agency science policies and ri s k assessment m ethodologies to prepare a quantitative ri sk assess ment in support of the regi s trat ion review of m etofluthrin. The mo s t re ce nt human h e alth ri sk assessment was co nducted in September 18 , 2012. For a detail e d di scu ss ion , see the Meto fl uthrin. Human Health Risk Assessment for the New Use to Control B ed Bugs and to Support R egistr ation Re view publi shed on June 26, 2013 in the public docket E PA

HQ

- OPP -2 012

-0105, which can be acces sed on http://www.regulations.gov/. 

### Hazard Characterization and Risk The Agency c ondu c te d a quantitati ve human health ri sk assessment fo r metofluthrin and found that there are no risks of concern associated with its use. A review of hum an incidents associated with the use of metofluthrin was conducted, and th e number and overall severity of the reporte d incidents were found to be low. 

### Dietary Risk Assessment There are no propo sed o r c urrently registered food u ses for metofluthrin. Further, drinking water exposure is not expected ba se d on the indoor use a nd limited o utdoor uses of metofluthrin; a dietary as sess ment is not needed. 

### Food Tolerances There are no established or propo sed tolerances for metofluthrin on or o n any food or feed crops. 

### Residential and Occupational Risk Assessment The Agency ha s d etermined that th ere are no re si denti al o r oc cupati on al risks of concern for metofluthrin.


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### Aggregate Risk Assessment Since there are no food uses for metofluthrin, an aggregate risk asses sment is not needed. Further , no exposure through drinking water is expected; the only relevant scenarios assessed related to residential and occupational expo s ure and risk, whi ch were not concern. 

### Cumulative Risk Assessment Although metofluthrin has been identified as be longing to the pyrethroid cumu lative group , the Agency has determined that metofluthrin will not contribute s ignificantly to expo s ure from the pyrethroids or change the overall find in gs from the cumulative risk assessment for the pyrethroid s. For inform ation regarding EPA 's efforts to evaluate the risk of exposure to pyrethroids, refer to http://www .epa. gov /oppsrrd 1/reeva lu ation/pyre throids

- pyrethrins

.h tml
. 

### Human Incidents Metofluthrin incident s were reviewed in 2012, and it was concluded that "overall the incident cases reported for metofluthrin were generally [o f] low frequency and low severity
... " The Agency has continued to monitor metofluthrin incident s . Base d on a more rece nt search conducted a nd reported in 2013, there have been 14 additional moderate incidents and one major incident reported to IDS s ince the previous review. In addition , four low severity cases reported to SENSOR-Pe sticide s were reviewed. The conclusion from the updated incident review is cons i stent with the previous co nclusion that incidents do not support a weight of evidence for human health risk. The Agency will continue to monitor the incident information and if a concern is triggered , additional analysis will be conducted. 

### B. Environmental Assessment A summary of the Agency's environmenta l risk assess ment for metofluthrin is presented below. For detailed discu ss ions of all aspects of the environmental risk asses s ment, see the Registration Review: Preliminary Ecological Risk Asses sme nt and Endange red Species Effects Determination for Metofluthrin, publi shed on June 26, 2013 , in the pub l ic do cket EPA-HQ-OPP

2012 -0105, which can be accessed on http://www.regu lations .gov /
.



### 6Environmental Fate and Exposure Metofluthrin i s released into the air from insect repellent products as a n aerosol or as vapor through passive di ss ipation or heat-or fan-driven evaporat i on. The active ingredient is ex pected to dissipate rapidly through a combination of degradation and dilution by the l arge volume of air into which it is released. Metofluthrin will photo-degrade in air with an estimated half

- life of less than 2 hours. The combined effects of the sma ll quantity of metofluthrin contained in each repellent devise, rapid degradation , and dilution in large vo lumes of air res ult in a low likelihood of sig nificant depos ition. Metofluthrin that is depo s ited on l and s urface s will have low pers i stence and low mobility. Because metofluthrin is used as an insect repellent and has in sectici dal properties, it i s a ss umed that non- target insects that are exposed to metofluthrin via ambient ex posure (i.e., flying through the metofluthrin released by an impregnated strip, fan, candle, or tabletop mister) have the potential to be repe ll ed, and perhap s kill e d. However, the l abels for the metofluthrin repellent produ c ts indi cate that they are effective over s mall areas only. Mosquitoes actively track humans in order t o obtain a blood meal so only metofluthrin produ cts used in close proximity to humans are effective. Bee s and other beneficial insects would not be expected to b e attracted to humans. Therefore, the y wou ld be exposed to the metofluthrin minimally, and primarily by chance. The amount of metofluthrin present on s kin and in the washwater of bed linens in contact with mattresses treated for bedb u gs is not expected to result in environmentally significant co ncentrations in s urface water. Metofluthrin that reaches water is stab le to hydroly s is in neutral and acidi c conditions but d eg rade s in alkalin e condition s and through photolysis. Due to its high so il/water partition coefficient , metofluthrin would tend to bind to soi l particle s rather than remain in the water co lumn

. In summary, the potential exposure of non-target organisms to metofluthrin fro m the c urrently registered u ses is expected to be low. Although the availabl e data were adequate for assessing the exposure associated with the current uses, additional data may b e needed in the future if the u se pattern (and, thus, t he exposure potential) for metofluthrin changes. Ecological Risk Characterization Aquatic Animals Because of th e limited opportunities for ex po s ure, as explained above, there are no ri sk s of concern for aquati c animals associated with the current uses of metofluthrin. Birds and Mammals All of the avai lable acute toxicity data for b irds and mammal s yielded non-definitive endpo ints (i.e. , "greater than " values) and indi cate that metofluthrin is practically non-toxic to these organisms (and by ex te nsion to reptiles and terrestri al-phase amphibians fo r which birds serve as s urrogate s). Additio n ally, all of the ex po sure va lues, conser vati ve ly esti mated using TREX, were well below the highest concentrations tested in the availabl e acute toxicity studies for
7terrestrial animal s. There are no ri sks of concern for birds and mammals associated with the current uses of metofluthrin. 

### Bees and other terrestrial insects Given the lik ely setting of use, the behavior of insects around human s, and the fate of metofluthrin in the environment, the probability of impacting bees and other non - target terrestrial ins ects is considered to be low. There is no reasonable expectation of effects. Toxicity information for beneficial in sects is used to develop precauti onary label language where neces sa ry . Based on the toxicity data alone , pr ecautionary label language for bees wou ld normally be recommended for th e outdoor u ses of metofluthrin. However, becau se of the limited exposure potential to bees from the registered metofluthrin u ses, the precautionary label language is not con s idered necessary. 

### Plants There are currently no data availab le to assess the potentia l risk to terres trial or aquatic plants from the registered metofluthrin uses . There is no rea sona ble expectation of effects to plants due to the low expo s ure potential. 

### Ecological Incidents To date, there are no re ported ecological incidents associat ed with metofluthrin based on a search of the data base conducted on June 6, 2012. 

### Endangered Species Assessment There i s no reasonable expectation for any registered use of metofluthrin to cause direct or indirect adverse effects to threatened and endangered species. No adverse modification of critical habitat is expected to occur from use of metofluthrin. This is because of the types and extent of use , the low toxicity shown by existing stu dies, the highly diffuse nature of the use site, and the extremely low annual u sage. EPA has made a "no effect" determinat ion under the Endangered S pe c ie s Act (ESA) for all liste d s pecies and their designated critica l habitat for s uch spec ies and has therefore co ncluded that consultation with the Fish and Wildlife Service and the National Marine Fisherie s Service under ESA section 7(a)(2) i s not required. 

### Endocrine Disruptor Screening Program EPA has developed the Endocrine Disrupter Screening Program (EDSP) to determine whether certain s ub stances (including pesticide active and other ingredients) may hav e an effect in humans or wi ldl ife sim ilar to an effect produced by a "naturally occurring es trogen, or other such endocrine effects as the Administrator may designate." Under FFDCA Section 408(p), the Agency mu st screen all pe sticide chemicals. Between October 2009 and November 2010, EPA issued te st orders/data call

- ins for the first group of 67 chemicals and publi sh ed a second li st of chemical s proposed for order issuance in the future. Metofluthrin was not among the group of 

### 58 pesticide act ive ingredients on the initial list nor is it 

### propo sed on the second list of chemical s to be screened under EDSP. According! y, as part of regi s tration review , EPA will i ss ue future


### 8EDSP orders/data call-ins for registration review chemicals, including metofluthrin. For further inf ormation on the s t atus of the EDS P , the policies and procedures, the li st of 67 chemicals, future chemical list proposed for screening, the test guidelines and the Tier 1 screening battery , please visit our website: http://www.epa.gov/endo/. In the interim , EPA is making no human health or environmental safety findings as s ociated with EDSP screening of metofluthrin. Before completing this Registration Review, the Agency will make an EDSP FFDCA section 408(p) determination. 

## III. Interim Registration Review Decision In accordance with 40 CFR Section s 155.56 and 155.58, the Agency is iss uing this Interim Registration Review Decision. Except for the EDSP component of the case, the Agency has made the following decision re l ative to registrations of metofluthrin: (l) no additional data are required at this time and (2) no changes to the affected registrations or their labeling are needed at this time. In addition, EPA doe s not expect metofluthrin to have direct or indirect adverse effects to non-listed and li sted species

. EPA ha s made a " no effect" determination under th e Endangered Species Act (ESA) for all listed species and designated critical habitat for su ch species. The Agency's final registration review decision for metofluthrin will occur after an EDSP FFDC A Section 408(p) determination.



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