### Fipronil Focus Meeting Notes

- Docket May 14 , 2013 1 :00

- 2 : 0 0 pm

Non

- EPA attendees BASF: Jack Arthur, Amy Dugger

- Ronyak , Charles Ha stings , Jeff Holmsen, Scott Jackson, Scott Lane , Spencer Mortensen Bayer: Ann Blacker, Jan Brill , Karen Sheerer Gharda Chemicals, LTD: Ram Seethapathi Hisun: James Messina (Exponent) Horizon Vally and Prodigy: Leanne Pruett (Pyxis RC) Irvita: Anne Turnbough (CSI) Norbrook: Lee Whaley Raymat Materials: Ia i n Weatherston (J&T Associates) Virbac: Michelle Foster

EPA attendee s RD: Richard Gebken PRD: Susan Bartow, Cathryn Britton, Kevin Costello HED: Wade Britton, William Irwin, Mike Metzger, Ideliz Negron, Shan na Recore, Ana Rivera

- Lupianez EFED: Ed Odenkirchen
, Robin Sternberg, Stephen Wente BEAD: Sepehr Haddad

Participating by phone BASF: Charlotte Sanson, Ralph Warren Gharda: Frank Sobotka Merial: Jim Gerhart, Jay Harriman, Karen Mardis



### 1. Introductions

2. Discussion of EPA’s “Focus” Questions The purpose of a focus meeting is to clarify use and label uncertainties early in the registration review

process. Several questions were provided to the registrant s before the meeting ( see below ) regarding fipronil use, application rates , and a required study

. These questions were discussed. The registrants
wi ll also provide written answers to the questions where possible

.

• Question 1

– Many of the labels give application rates in mass/placement for outdoor bait station

a pplications. OPP would assume that the fipronil is removed by the insects and spread out o ver a surface area of land (i .e., in the insect carcasses). Therefore, we would need to know the number of placements per acre, 100 ft 2 , or 1000 ft 2 and how frequently the bait is replaced to calcula te an annual application rate. Does the registrant have any information on this? Would they be willing to put it on their labels?

- Bayer is the only registrant with the outdoor bait station use. Bayer representatives indicated that they did not have data to directly answer the questions , but offered biological opinions in writing.• Question 2

– The Frontline spray treatment product application rate for cats and dogs is given as 2 pump/1 lb body wt. Is this similar to a spot treatment (applied to a sm all area of the animals back)? This may be a use that would not trigger an ecological assessment, but it would be g ood to discuss at the meeting. If we were to assess, the application rate would need to be converted to mass of A.I./1 lb body wt. In that case, do the registrants have any recommendations for better estimating the application rate?

- The registrant, Merial, provided a written response to this question.

• Question 3

– Several uses (christmas tree plantations, forest trees (softwoods, conifers), ornamental and/or shade trees, ornamental herbac eous plants, ornamental non

- flowering plants, ornamental woody shrubs and vines, and potting soil/topsoil) have application rates in lbs/ft 3 (mass/volume). Do the registrants have any recommendations for estimating maximum mass/area? Are all of these

use s associated with potted plants? OPP would probably assume a 6 inch depth of soil to convert to mass/area. Is this appropriate in the registrants’ view?

- Bayer representatives responded that they did not have an objection to the 6 inch depth and that the y would provide information regarding a maximum mass/unit area.

• Question 4

– Several uses (commercial/institutional/industrial premises/equipment (outdoor), household/domestic dwellings outdoor premises, industrial/construction areas (outdoor),
ornamental and/or shade trees, and wood protection treatment to buildings/products outdoor) have application rat es in lbs/gal (mass/volume). Do the registrants have any recommendations for estimating maximum mass/area?

- OPP agreed to provide product numbers for the specific uses in question.

• Question 5

– USEPA calculated application rates for the drainage syst em use are over 1,000 lbs/acre. Rates have also been calculated as mass/drain

. Do the registrants have any recommendations for better estimating maximum mas s/area? Potentially, it may be that OPP simply needs more information or a better description of this use.

- OPP agreed to provide product numbers for the specific products with the use in question.

• Question 6

– Many of the labels give application rates i n volume/mo und for fire ant applications. OPP would assume that the fipronil is removed by the insects and spread out over a surface area of land (i .e., in the insect carcasses). Therefore, we would need to know the number of mounds per acre, 100 ft 2 , or 1000 ft 2 to calcula te an annual application rate. Do the registrants have any
information on this? Would they be wil ling to put it on their labels? Also, regarding ant mound treatments, information on the number of mounds treated per surface area would be beneficial for

our assessments.

- The registrants indicated that non

- bait fipronil products are not used for fire ant mound

treatment . Labels should be verified to see if this use is still listed.• Question 7

– According to the recent AHETF Se ed Treatm ent Survey, corn seed is treat ed for over 240 days per year. Is fipronil being used to treat corn seed all year round?

- The registrants indicated that 240 days per year was an extremely high estimate. Fipronil is only used to treat corn seed for export. BASF representatives indicated that they would check with the end users to get an accurate number of days that fipronil is used to treat corn seed

.

• Question 8

– OPP would like to discuss the 90

- day dermal study (870.3250) with respect to HASPOC
recommend ations for the study. In January, 2012, the HASPOC provided recommendations for the study (TXR # 0056207). Specifically, the text from the document recommended,

“ IV. HASPOC RECOMMENDATIONS:

The HASPOC agreed with the team that a 90

- day dermal study is required for fipronil for the following reasons: (1) repeated intermediate

- term (1

- 6 month) exposure to fipronil is likely based on the use pattern an d updated Residential SOPs; (2) there is increasing toxicity with exposure duration, and thus the 21

- day study is not adequate to assess exposures up to 6 month; and (3) extrapolating from a subchronic oral rat study is not appropriate because the rabbits appear to be significantly more sensitive than the rat and a dermal study of appropriate duration (i.e., 90 days) is not available in this species.

Based on these considerations the HASPOC recommended a 90

- day dermal toxicity study in rabbits (870.3250) and the study should measure appropriate parameters (hormones, enzymes, weights and histopathology) relat ed to the toxicity of the tar get organs (thyroid and liver). In addition, the HASPOC recommends the team should review the existing 21

- day dermal study as well as the toxicity endpoints selected for risk assessments.”



### - The group discussed the request to c onduct the study with rabbits rather than rats. The registrants proposed to submit an in vitro data comparison to support species selection for this study. OPP agreed to review and consider the registrant’s proposal

.

3. Wrap up and Next Steps

• OPP discussed the Agency’s policy change to assess short, intermediate, and long

- term durations of exposure for spot on treatment products and pet collar products.

• The r egistrant s indicated that it was unclear if all of the end use registrants are aware of registration
review.

• OPP agreed to clarify whether the 90

- day dermal study required in the registration review DCI
should be conducted with TGAI or TEP.

• The registrants indicated that they were planning to finalize the Fipronil Task Force membership in early June.