UNITED STATES ENVIRONMENTAL PROTECTION AGENCY WASHINGTON D.C., 20460

PC Code: 129093 DP Barcode: 423209 Date: October 28
, 2014

MEMORANDUM

SUBJECT:

FROM:

THROUGH:

TO: Response to Public Comments on the Registration Review: Preliminary Ecological Risk Assessment and Endangered Species Effects

- Det ermination for C hl orfenapyr


### Stephen Wente, Ph.D., Biologist 

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# ;;~ Environmental Risk Branch I 

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Environmental Fate and Effects Division (7507P) Office of Pesticide Program s**~~** Sujatha Sankula, Ph.D.
, Branch Ch i ef .1

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# ..**~** Meghan Ra dtke
, Ph.D.
, Acting RAPL

## ~~~ 10 Envi r onmental Risk Branch I Envi ron mental Fate and Effects Division (7507P) Office of Pesticide Programs

Margaret Hathaway, Chemical Review Manager Tom Myer s, Team Leader Kevin C ostello, Branch Chief R isk Management and Implementation Branch 2 Pesticide Re-Evaluation Di v i sio n (7508P) Office of Pesticide Programs

In response to the " Registration Review: Preliminary Eco log ical Risk Assessment and E ndangered Spec ie s Effects Determination for Chlorfenapyr" (D 420682), the Agency received two comments from The Center for Biological Diversity and an anonymous commen ter. The purpose of this memorandum i s to address these comments.

Comme nt from Tbe Center for Biological Diversity

Comme nt: " The draft ecolog i ca l risk assessment for Chlorfe nap yr concluded that " Ba s ed o n incomplete exposure pathways for all chlorfenapyr uses , the Agency makes a No Effects (NE) determination for all li sted species as well as a No Habitat Modification determination for all designated c ritical habitats for t he

c urren tly registered u ses of c hl orfe napyr. " The Center for Biological Diversity s upp orts this determination and agrees that co n s ultations under Section 7 are not required for this pesticide."

EPA response: The A g ency appreciates the acknowledgement o f concurrence

.

### 2 Comment from the Anonymous Commenter

Comment: “Chlorfenapyr is registered for application to mu ltiple sites with direct and indirect pathways to sewage treatment plants. These sites include crack /crevice/spot treatment on indoor residential sites (including as a bed bug treatment), food/feed handlin g areas, indoor commercial sites (including sewers), and indoor medical sites. Direct discharge would occur from sewer treatment; indirect discharges would occur from cleaning treated surfaces. Sewage treatment plants discharge to the environment, both to surface waters and to biosolids use locations (e.g., ag ricultural fields). Sewage treatment plants are not designed to degrade pesticides, which are commonly found in both effluents and biosolids.

Chlorfenapyr is registered for application outdoors, including crack/crevice/spot treatment on outdoor residential sites. Rainwater falling on these outdoor locations could potentially wash chlorfenapyr and/or its degradates directly to surface waters, without any treatment, through municipal storm drainage systems (which are often composed entirely of impervious surfaces and hard drain pipes).

The existence of these pathways indicates that th e "no environmental exposure" analysis is not appropriate for a chemical with the above use sites.

I encourage OPP to update its exposure assessment methodologies to more accurately reflect urban environments. 1 

### ”

EPA response: The comment addresses two different, but related issues. The first points out that many of the listed chlorfenapyr uses “sound like” outdoor u ses that could result in exposure to ecological receptors. The Agency addressed this concern for several of the uses that had confusing use site descriptions on pages 4 and 5 of th e Chlorfenapyr Problem Formulation 2



### . ...these use group names may appear to result in outdoor exposures to ecological receptors:

 Household/Domestic Dwellings Outdoor Premises (Outdoor Residential) and Nonagricultural Outdoor Buildings/Structures (Terrestrial Non-Food Crop) – refers to uses that form a zone or barrier in the soil surrounding a building or structure (under concrete slab flooring and adjacent to ba sement walls) during construction and crack and crevice treatments that are used on exi sting buildings and structures. Preconstruction uses of chlorfenapyr result in the pesticide sequestered by soils under the floor of, or adjacent to the basement walls of, a building. Post-construction and crack and crevice treatments are limited to a 9.4 × 10 -5

### lbs ai per 2 sq. feet every four weeks. Therefore, assuming 4 sides of a building are treated with sides 10' high by 100' long (4000 ft 2 

### ) would result in a maximum treatment of 0.18 lbs ai to the building. However, EFED believes such applications would be unlikely to create a significant exposure pathway to ecological receptors because: mo st structurally sound buildings have far fewer cracks and crevices than the maximum application rate allows; much of the applied pesticide would be retained inside th e crevice or crack; and much of the pesticide that was dislodged from its application si te would be retained in any soil and/or landscaping at the base of the treated wall.

1 http://www.regulations.gov/#!documentDetail;D=EPA-HQ-OPP-2010-0467-0022
2USEPA. Registration Review – Problem Formulation Revised Based on Public Comments for Ecological Risk, Environmental Fate, and Endangered Species Assessments for Chlorfenapyr (PC Code 129093; DP Barcode 383511). Office of Pesticides Programs. 10/28/2010.

### 3  Sewage Systems (Aquatic Non-Food Industrial) – is a crack and crevice treatment that is used in cracks in the concrete slab flooring ar ound floor drains. The intent is not to discharge the chemical to the sewer system but, rather, to prevent ground-dwelling insects from entering a building through cra cks in the flooring around the drain. The label specifies that the drain must lead to a sewage system (and thus presumably, would be greatly diluted if some of the pesticide we nt down the drain) to prevent the use of the chemical around drains that may discharge immediately outside of the building (where relatively little dilution might occur).

 Zoos (Indoor Non-Food) – is also a crack and crevice use that is used on buildings enclosing zoo animals.

The commenter’s second issue conflates the Agency’s use of the phrase “incomplete exposure pathway” with the idea of no (zero) exposure. The Agency uses the phrase “incomplete exposure pathway” to indicate that any potential exposure to an ecological receptor (non-target organism) through registered (legal) uses of a pesticide would be far below the level necessary to cause harm to that receptor. For example, use of chlorfenapyr in a crack and crevice treatment around floor drains likely results in small and infrequent releases of chlorfenapyr to wastewat er treatment plants (WWTP) when the floor is washed. However, the exposure to aquatic life in the receiving water from a WWTP or to terrestrial organisms from land applied WWTP soli ds would most likely be far below that necessary to cause harm.

Again as stated in the Chlorfenapy r Problem Formulation, based “on incomplete exposure pathways for all chlorfenapyr uses, the Agency makes a No Effects (NE) determination for all listed species as well as a No Habitat Modification determination for all design ated critical habitats for the currently registered uses of chlorfenapyr.”